26 p. : ill ; 24 cm.Includes bibliographical references (p. 26)

Myers, Frank Jacob.

8 p. : ill ; 24 cm.Includes bibliographical references

American Museum of Natural History Scientific Publications

AMERICAN MUSEUM NOVITATESPublished byNumber 761 THE AMERICAN MUSEUM OF NATURAL HISTORY Dec. 29, 1934New York City59.51, 8 T (74.1)THE DISTRIBUTION OF ROTIFERA ON MOUNT DESERTISLAND. PART VII'NEW TESTUDINELLIDAE OF THE GENUS TESTUDINELLA AND A NEWSPECIES OF BRACHIONIDAE OF THE GENUS TRICHOTRIABY FRANK J. MYERSAs was the case with several other genera, the waters of MountDesert Island contained an unsuspected number of new testudinellids.The anatomy and the trophi are very constant throughout the genus.The salient characters are to be found in the lorica of fully contractedspecimens. They are: the general shape and size, the shape of theanterior and mental margins, the position of the lateral antennae, theposition and shape of the foot opening, and the shape of the transversesection of the body. The trophi are of the malleo-ramate type.The new species described in this paper are as follows:Testudinella angulata Testudinella dentataTestudinella triangularis Testudinella ovataTestudinella epicopta Testudinella dicellaTrichotria eukosmetaORDER MONOGONONTAFamily TestudinellidaeTestudinella angulata, new speciesFigures 1, 2The lorica is roughly triangular and ovate, narrowest anteriorly, then graduallywidening to a position marked by the lateral spines. The posterior portion is evenlyrounded and marked by a median blunt projection of the foot opening. There are apair of lateral spinules situated at the point of the greatest body width. The dorsalanterior margin is roughly trilobed, the median lobe being more prominent and acutethain the lateral lobes. The mental margin is undulate; it has a small bluntmedian lobe bounded by larger laterals.The lateral antennae are situated on the dorsum about half way between theanterior and posterior margins of the lorica.The foot opening is elongate, oval, and terminal.'The preceding parts of this article appeared in American Museum Novitates as follows: part I(not numbered) in No. 494. Sept. 28, 1931; part II in No. 659, Sept. 15, 1933; part III in No. 660,Sept. 15, 1933; part IV in No. 699, March 10, 1934; part V in No. 700, March 10, 1934; part VI inNo. 760.AMERICAN MUSEUM NOVITATESThe transverse section of the lorica is greatly depressed and its exact shape willbest be understood by reference to figure 2.Length of lorica, 130%u. Width of lorica at widest part, 90,u; anterjor margin,60,u.Testudinella angulata was fairly common throughout the island inassociation with submerged Sphagnum and Fontinalis. It has also beencollected in Vilas County, Wisconsin, and in Atlantic County, NewJersey.In Testudinella parva (Ternetz), lateral spines may be present orabsent. The form having lateral spines is now recognized as a varietyand is known as Testudinella parva bidentata (Ternetz). In Testudinellaangulata the lateral spines are constant and always present.The type is deposited in The American Museum of Natural History;Cat. No. A M.N.H. 390.Testudinella triangularis, new speciesFigures 3, 4The body is roughly triangular and ovate in shape. The posterior portion istruncate, slightly rounded and marked by a median notch of the foot opening. Thereare a pair of lateral spines, situated relatively lower down than in the preceding species,and nearly opposite the anterior limit of the foot opening. The dorsal anterior marginprojects strongly, is bluntly pointed and has a median notch dividing it into two lobes.The mental margin is excavate and widely V-shaped. The lateral antennae aresituated low down in the lumbar region.The foot opening is subsquare and terminal.The transverse section is triangular; the lateral edges are rounded and there is alow median keel extending the entire length of the venter.Length of lorica, 120%u. Width of lorica at widest part, 88,u; anterior margin,40,u.Although Testudinella triangularis was not as common as the preced-ing species, it was evenly distributed throughout the Island in similarassociations. It has also been collected in Atlantic County, New Jersey,and was abundant in Wheeler Lake, Vilas County, Wisconsin, duringseveral summers. It bears a superficial resemblance to Testudinellaangulata, but differs from that species principally in the anterior marginsand in the transverse section of the lorica.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 760.Testudinella epicopta, new speciesFigures 5, 6The body is squarely truncate anteriorly and posteriorly, widest in front anddiminishing gradually from mid-length to the foot opening. The anterior dorsal marginis nearly straight; the mental margin is slightly undulate and has a shallow central2 [No. 7611934] ROTIFERA ON MOUNT DESERT ISLAND. VIInotch. The lateral antennae are situated nearly opposite the middle of the longi-tudinal body axis.The foot opening is narrow, very wide and terminal.The transverse section of the lorica is relatively stout; its exact shape will bestbe understood by reference to figure 6.Length of lorica, 90u. Width of body at widest part, 75,; anterior margin, 65,u.Testudinella epicopta was evenly distributed throughout the island.It is commensal on the cladoceran Acantholeberis curvirostris, and wasgenerally found attached, by the ciliated tip of the foot, to the posteriorportion of the carapace. It has also been collected in Atlantic County,New Jersey, and in Vilas County, Wisconsin.This is not the only species of the genus that has developed the habitof commensalism. Testudinella elliptica Ehrenberg, Testudinella caeca(Parsons) and Testudinella truncata (Gosse), are to be found attached tothe legs and gill plates of Asellus.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 455.Testudinella dentata, new speciesFigures 7, 8The body is ovoid and truncate anteriorly. The dorsal anterior margin is convexand projects in the form of two low lobes. The mental edge is slightly undulate andhas a deep median sinus bounded by two acute spines. The lateral antennae aresituated slightly above the median transverse body axis.The foot opening is narrow and situated on the posterior fifth of the venter.The transverse section of the body is much compressed, stouter in the middleportion and rounded at the lateral edges.Length of lorica, 150,u. Width of lorica at widest part, 90/A; anterior margin,75,u.Testudinella dentata was common in brackish water near the outletof the Barcelona at Thomas Cove. It has also been collected in brackishwater in Powell's Creek, Atlantic County, New Jersey. It bears acertain resemblance to Testudinella clypeata Ehrenberg, which also hasbeen found in salt and brackish water. It differs from that species inhaving a notched anterior margin, instead of being simply convex; thetransverse section of the lorica is symmetric both dorsally and ventrally,instead of being convex dorsally and having a much smaller convexventral side.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 140.31 32411798c 7~~~~113Fig. 1. Testudinella angulata, dorsal view of lorica. Fig. 2. Transverse section.Fig. 3. Testudinella triangularis, dorsal view of lorica. Fig. 4. Transverse section.Fig. 5. Testudinella epicopta, dorsal view of lorica! Fig. 6. Transverse section.Fig. 7. Testudinella dentata, dorsal view of lorica. Fig. 8. Transverse section. Fig.9. Testudinella ovata, dorsal view of lorica. Fig. 10. Transverse section. Fig. 11.Testudinella dicella, dorsal view of lorica. Fig. 12. Transverse section. Fig. 13.Trichotria eukosmeta, lateral view. Fig. 14. Dorsal view of posterior portion of body.Dotted lines are features of the venter.456-1934] ROTIFERA ON MOUTNT DESERT ISLAND. VIITestudinella ovata, new speciesFigures 9, 10The body is elongate and oval in shape. The dorsal margin is strongly convexand disposed into four prominent lobes. The mental margin is excavate and widelyV-shaped. The lateral antennae are situated nearly opposite the first third of thelongitudinal body axis.The foot opening is wide and semicircular in shape; it is situated on the posteriorfifth of the venter. There is a low ventral elevation, starting at the apex of the V-shaped mental margin, which gradually widens and terminates at the foot opening.The transverse section of the lorica is nearly straight dorsally and bluntly keeledventrally: its exact shape will best be understood by reference to figure 10.Length of lorica, 125u. Width of lorica at widest part, 90MA; anterior margin, 55u.Testudinella ovata was not common. A few specimens were col-lected in several locations at different ntervals, always in associationwith submerged Sphagnum.The projecting four-lobed anterior margin and the longitudinalventral elevation readily distinguish this from any other species of thegenus.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 739.Testudinella dicella, new speciesFigures 11, 12The lorica is greatly depressed, urn-shaped, and has a prominent median, pos-terior, subsquare projection. The dorsal anterior margin is undulate; it is boundedlaterally by two out-curved spines and has a prominent angular, median projection.The mental margin is undulate and has a wide subsquare median sinus boundedlaterally by two blunt spines. The lateral antennae are situated somewhat above themedian transverse body axis.The foot opening is terminal and protected dorsally by a prominent subsquareprojection of the dorsum.The transverse section of the lorica is greatly compressed, straight dorsally andwidely angular ventrally.Length of lorica, 130,u. Width of lorica at widest part, 85u; anterior margin, 78,u.Testudinella dicella was fairly common and well distributed on theisland. It has also been collected in abundance in the Pocono Moun-tains, Pennsylvania, Vilas County, Wisconsin, and Atlantic County,New Jersey.Although this species seems to be closely related to Testudinellatridentata Smirnov, from which it differs principally in the details of theanterior margins and the shape of the lorica, it seems justifiable to nameit as a new species, in view of the fact that Smirnov (1) does not show the5AMERICAN MUSEUM NOVITATESlocation of the lateral antennae nor does he give a transverse section ofthe lorica, both very important in the determination of species.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 261.Family BrachionidaeTrichotria eukosmeta, new speciesFigures 13, 14The body is slightly gibbous dorsally. The lorica is minutely punctate and quiteflexible. The posterior portion of the dorsum is acuminate from the dorsal view; fromthe lateral view it terminates in a prominent recurved, bifid projection.The foot has two joints; the basal joint is stout and conical and bears two longacute condyles on its dorsal surface. The toes are blade-shaped, slightly decurved andparallel-sided; they are about equal to the foot in length.The lateral antennae are guarded by a prominent hook-like spine. The dorsalantenna is a prominent papillose projection from which emerges a tuft of sensorysetae.The mastax is malleate and the anatomy agrees with that of the other membersof the genus.Total length, 220,u; toes 30,.&A few specimens of Trichotria eukosmeta were collected in FawnPond during the summer of 1926. It has not been found again.Although the other members of the genus Trichotria are notablefor the thickness of the lorica, which is always marked by facets, theintegument of this species is thin and flexible without any traces offaceting. Trichotria tetractis caudata (Lucks) has a posterior pointedprojection of the lorica, but it is never bifid from the lateral view. More-over, that variety has a normal faceted lorica and closely resemblesTrichotria tetractis (Ehrenberg).The type is deposited in The American Museum of Natural History;Cat. No. A. M.N.H. 653.GENERAL REMARKS ON DISTRIBUTION OF ROTIFERSAlthough it is true that there seem to be a number of species that areindigenous to the separate localities, the rotatorian faunas of MountDesert Island, Vilas County, Wisconsin, and Atlantic County, NewJersey are strikingly similar. The various bodies of water includedin the three localities range in pH from 3.5 to 6.8 in the littoral regions.Therefore, the fauna is an acid water fauna and most of the speciesof such typical alkaline genera as Brachionus, Mytilina, Eosphora,Notholca, Asplanchna, Lacinularia and Sinantherina are practicallyabsent; at least they are only represented by occasional stragglers.6 [No. 7611934] ROTIFERA ON MOUNT DESERT ISLAND. VIIMETHODS OF COLLECTION AND STUDYIn describing new species preference has been given to those whosehabitats are also Wisconsin and New Jersey. There remain a number ofprovisional species that may be indigenous and new. These have beenleft in abeyance until such time as more is learned about them byfuture research.In view of the fact that such a large number of species were recorded'from an island of only one hundred and five square miles in area, a noteon the method of collecting will not be amiss.It was decided, in order to be as accurate as possible in the de-termination of species and the description of new ones, to examine allmaterial in the living state. Therefore it was necessary to transport thespecimens collected to the laboratory as quickly as possible, instead ofnarcotizing and fixing the material in the field, as is frequently done.Aquatic plants were gently lifted above the surface and placed inwide-mouthed jars of 1000 cc. capacity, containing water from the samesource, care being taken not to crowd too much. This trapped the rotifersamong the leaves while washing off most of the undesirable organisms,such as Entomostraca, insect larvae, and aquatic worms. In such collec-tions the change in environment is not too sudden, but takes placegradualiy, while the food and safety factors are maintained better thanin clear collections which have been concentrated by means of a net offine mesh. The net was only resorted to occasionally in the absence ofaquatics. Thousands of organisms are introduced into the containerswith the plants. Animal death and post-mortem changes begin to takeplace at once. Therefore, in order to work over the collections whilethey were as fresh as possible, and in view of the fact that virtually allof the locations were bounded by good roads, an automobile was inconstant use 'or transporting the collections to the laboratory. Onarrival, the containers were placed several feet from the source of light.The heavier vitiated water gradually sank to the bottom and the lighterpurer water rose to the top. After a certain interval, depending on thetemperature, the rotifers came out from among the plants and ascendedwith the fresher water; they eventually reached the surface and assem-bled on the side nearest the light and crowded into the meniscus, fromwhich they were removed and transferred to watch glasses. Virtually90 per cent of all the rotifers listed were collected in the above manner.Material of the species described in Parts VI and VII have beenplaced in the collection of The American Museum of Natural History.All investigations and research work on the Rotifers of Mount78 AMERICAN MUSEUM NOVITATES [No. 761Desert Island were carried on at the Wier Mitchell Station of the MountDesert Island Biological Laboratory, situated at Salisbury Cove, Maine.The author wishes to express his appreciation and thanks for the manycourtesies enjoyed and pleasant associations formed there during thesummers of 1921 to 1931 inclusive.BIBLIOGRAPHY(1) SMIRNOV, N. 1931. 'Deux nouvelles especes de Rotatoriens, provenant de laregion de l'Oussouri.' Comptes Rendus de l'Acad. Sci. de l'Urss.,pp. 54-58, Text Figure.

Rotifera on Mount Desert Island.

16 p. : ill ; 24 cm.Includes 1 bibliographical reference (p. 16)

10 p. : ill ; 24 cm.Includes bibliographical references (p. 10)

AMERICAN MUSEUM NOVITATESPublished byNumber 760 THz AMERICAN MUSEUM OF NATURAL HISTORY Dec. 28, 1934New York City59.51, 8 L (74.1)THE DISTRIBUTION OF ROTIFERA ON MOUNT DESERTISLAND. PART VI'NEW BRACHIONIDAE OF THE GENUS LEPADELLA2BY FRANK J. MYERSThe rotatorian fauna of Mount Desert Island proved to be veryrich in lepadellids, particularly in those species that lurk or live amongthe leaves of submerged aquatic mosses, especially Sphagnum. Fromsuch habitats all of the species herein described were collected. Individu-als were studied from fully contracted specimens, as the anterior margins,obscured in expanded animals, offer some of the salient characters in thedetermination of species. No detailed study of the corona or the trophiwas made, as they are very uniform throughout the genus. The coronais of the typical family type with the circumapical band suppresseddorsally because of the protective " head-hood." The mastax is malleate.No observations were made on the sensory pit, situated dorsally onthe terminal foot joint. As Harring (1) observed, "this sensory pit hasnot been demonstrated in all the species, but has been found in all caseswhere it was possible to obtain a properly oriented view under sufficientmagnification." The presence of a caudal ganglion among the rotifershas been demonstrated and it is not unreasonable to suppose that thesensory setae of the pit are connected with the ganglion by a nervethread, as in other genera.The lateral antennae, which emerge through simple openings on thedorsal plate near the posterior end, are very uniform throughout thegenus; no mention has been made of them in the descriptions, except inone instance which is explained in the text.The eight new species and two new varieties described in thispaper are as follows:Lepadella bractea Lepadella apsicoraLepadella venefica Lepadella xenicaLepadella longiseta Lepadella visendaLepadella triba Lepadella latusinus var. americanaLepadella akrobeles Lepadella triptera var. alata'The preceding parts of this article appeared in American Museum Novitates as follows: part I(not numbered) in No. 494, Sept. 28, 1931; part II in No. 659, Sept. 15, 1933; part III in No. 660,Sept. 15,1933; part IV in No. 699, March 10, 1934; part V in No. 700, March 10, 1934.aIn this and the following paper of the Mount Desert series, the classification of Remane (Bronn'sTierreich, IV, Abt. II, Buch 1, Rotatorien, Gastrotrichen und Kinorhynchen, pp. 514-517), has beenfollowed. I consider this the most natural and logical classification thus far proposed.AMERICAN MUSEUM NOVITATESORDER MONOGONONTAFamily BrachionidaeLepadella bractea, new speciesFigures 1, 2, 3The body is subcircular in outline, deep, strongly convex dorsally and evenlyarched; it is prolonged posteriorly into a small pointed projection. There is a promi-nent dorsal, zigzag keel arising near the anterior margin and extending the full lengthof the dorsum. The dorsal sinus is broadly U-shaped and has a well-marked stippledcollar. The ventral sinus is about twice as deep as the dorsal, and has an inconspicu-ous line running parallel to it marking the collar limit.The foot groove is elongate-oval in shape and rather short and narrow; its widthis little more than one-half of the length. The terminal foot joint is almost equal tothe combined length of the first and second joints. The toes are relatively short andtaper gradually to acute points.Length of lorica, 78MA; foot groove, 21uA; foot, 18,u; terminal foot joint, 9/A;toes, 21,. Width of lorica, 68,u; anterior points, 25,u. Depth of dorsal sinus, 12ju;ventral sinus, 24,u.Lepadella bractea was fairly common throughout the island; ithas also been collected in Atlantic County, New Jersey, and Vilas County,Wisconsin. The species is easily recognized by the prominent dorsalzigzag keel which gives the impression of being too long for the body andhaving become compressed longitudinally in order to fit. It is, however,a natural and permanent character and every individual, including thosefrom New Jersey and Wisconsin, was thus provided.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 80.Lepadella venefica, new speciesFigures 4, 5, 6The body is ovate in outline, fairly deep and evenly arched dorsally. Theanterior margin is straight and there is no stippled collar present. The ventral sinus isdeep and broadly U-shaped; it is provided with a flaring collar, but no stippling wasobserved.The foot groove is wide and parallel-sided. The terminal foot joint is slightlylonger than the combined length of the first and second joints. The toes are short,fairly stout and taper regularly to acute tips.Length of lorica, 57,u; foot groove, 15u; foot, 15,A; terminal foot joint, 7/A;toes 14,/. Width of lorica, 47/A; anterior points, 20/A. Depth of ventral sinus, 10/o.Lepadella venefica was evenly distributed throughout the island;it is also common in Atlantic County, New Jersey. This is one of thesmaller species, being only slightly larger than Lepadella triptera Ehren-berg. Like that species it is so small that it is difficult to find, and isprobably more common than the published records indicate. It differs2 [NO. 760I327 856910 12 11Fig. 1. Lepadella bractea, dorsal view. a, anterior points. Fig. 2. Ventral view.Fig. 3. Cross section of body. Fig. 4. Lepadella venefica, dorsal view. Fig. 5. Ven,tral view. Fig. 6. Cross section of body. Fig. 7. Lepadella longiseta, dorsal view.a, lateral antenna. Fig. 8. Ventral view. Fig. 9. Cross section of body. Fig. 10.Lepadella triba, dorsal view. Fig. 11. Ventral view. Fig. 12. Cross section of body.3AMERICAN MUSEUM NOVITATESchiefly from the above-mentioned species in the absence of a dorsal keeland in having a straight anterior, dorsal margin.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 382.Lepadella longiseta, new speciesFigures 7, 8, 9The lorica is ovate in outline, deep and evenly arched dorsally. The dorsalanterior margin is straight and no stippled collar was observed. The ventral sinus isdeep and broadly V-shaped; it is provided with a prominent stippled collar, the edgesof which are broadly flaring.The lateral antennae are in the normal position, and the sensory setae emergefrom the tips of small tubules.The foot groove is relatively short and oval in outline. The terminal foot jointis slightly longer than the combined length of the first and second joints. The toesare relatively very long and slender, tapering regularly from the base to very slendertips.Length of lorica, 78uA; foot groove, 20u; foot, 18,u; terminal foot joint, 12,A;toes, 38u. Width of lorica, 65A; anterior points, 28,u. Depth of ventral sinus, 16u.Lepadella lon'giseta is evidently rare. Two specimens were found inthe Witch Hole during the summer of 1930. This species is related toLepadella benjamini Harring, from which it differs in its much smallersize. While the depth of the body is ample, it is not nearly so deep rela-tively as that of the above-mentioned species, nor do the edges of thelorica overhang.The lateral antennae are characteristic. The tubules, from the tipsof which emerge sensory setae, are quite small, yet they are conspicuousenough to be easily seen, and are the only instance of this kind among thedifferent species of the genus.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 738.Lepadella triba, new speciesFigures 10, 11, 12The body is very elongate and oval; it is shallow and evenly arched dorsally.The anterior margin is nearly straight and there is no stippled collar. The ventralsinus is broadly V-shaped, with an inconspicuous line running parallel to it markingthe collar limit. The venter is provided with a very low, rounded elevation, and incross section somewhat resembles the lorica of Euchlanis. However, there are nolateral sulci, the entire ventral plate being hardened.The foot groove is flaring. The terminal foot joint is almost equal to one-half thelength of the toes. The toes are long and taper regularly to very slender, drawn outtips.4 [No. 7601934] ROTIFERA ON MOUNT DESERT ISLAND. VILength of lorica, 80,A; foot groove, 20,A; foot, 26uA; terminal foot joint; 14,A;toes, 32,A. Width of lorica, 45A; anterior points, 24u. Depth of ventral sinus, 12,u.Lepadella triba was found in a pool on Pond Heath, where severalspecimens were collected during the summer of 1926. It is readily distin-guished from the remaining species of theigenus by the very elongatelorica and the peculiar Euchlanis-like formation of the ventral plate.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 670.Lepadella akrobeles, new speciesFigures 13, 14, 15The body is elongate and oval in outline; it is shallow and has a low roundeddorsal elevation, widest near the anterior margin, then gradually diminishing inbreadth to the posterior margin, where it ends in the form of a low flange. Theanterior dorsal margin is very shallow and there are no indications of a stippled collar.The ventral sinus is broadly V-shaped and has an inconspicuous line running parallelto it, which marks the collar limit.The foot groove is narrow and parallel-sided. The terminal foot joint is slightlylonger than the combined length of the first and second joints. The toes are short andrather stout; they taper gradually to very slender tips.Length of lorica, 90/A; foot groove, 26/A; foot, 22/A; terminal foot joint, 12,/;toes, 24/A. Width of lorica, 68/A; anterior points, 28/A. Depth of ventral sinus, 15/A.Lepadella akrobeles was collected sparingly in an old, abandonedice pond near Manset, during the summer of 1930. The peculiar shapeof the dorsal elevation is distinctive and distinguishes it from any otherspecies of the genus.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 723.Lepadella apsicora, new speciesFigures 16, 17, 18The body is oval in outline, shallow, and evenly arched dorsally. The dorsalanterior margin is nearly straight and there is a prominent stippled collar. The ventralsinus is deep and broadly V-shaped; it is also provided with a prominent flaring collarwhich is stippled throughout.The foot groove is wide and slightly flaring posteriorly. The terminal foot jointis extremely long, being nearly twice the combined length of the first and secondjoints; it is twisted, as in Lepadella cyrtopus Harring, so that the left toe is almostdirectly under the right. The toes are strongly asymmetric, the right being nearlytwice as long as the left.Length of lorica, 80/A; foot groove, 21/A; foot, 30/u; terminal foot joint, 20/A;right toe, 30/A; left toe, 14/A. Width of lorica, 65/A; anterior points, 28/A. Depth ofventral sinus, 18/A.51913 1614 171815 21Fig. 13. Lepadella akrobeles, ventral view. Fig. 14. Dorsal view. Fig. 15.Cross section of body. Fig. 16. Lepadella apsicora, dorsal view. Fig. 17. Ventralview. Fig. 18. Cross section of body. Fig. 19. Lepadella latusinus var. americana,dorsal view, Fig. 20. Ventral view. Fig. 21. Cross section of body.61934] ROTIFERA ON MOUNT DESERT ISLAND. VILepadella apsicora was collected sparingly in the Witch Hole andAunt Bettie Pond during several summers. Its nearest relative is Lepa-della cyrtopus Harring, from which it differs mainly in the shape of theventral sinus and in the relatively longer toes. In Lepadella apsicorathe terminal foot joint is by far the longest, while the second foot jointis the longest in Lepadella cyrtopus.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 675.Lepadella latusinus var. americana, new varietyFigures 19, 20, 21The body is subrhomboidal in outline, and deeply and evenly arched dorsally.The dorsal anterior margin is slightly excavate and the outline is somewhat convexin the middle portion. No dorsal stippled collar was observed. The ventral sinus isdeep, broadly V-shaped, and has a prominent flaring-collar which is stippled through-out. The posterior margin of the dorsum is wide and flaring, slightly excavate andconvex in the middle portion.The foot groove is deep and widely flaring. The length of the terminal foot jointis nearly equal to the combined length of the first and second joints. The toes are ofmedium length and gradually taper to very acute tips.Length of lorica, 901u; foot groove, 24u; foot, 19A; terminal foot joint, 9,u;toes, 24/A. Width of lorica, 63,A; anterior points, 25,u. Depth of ventral sinus, 20,u.This variety is fairly common on the island, and also in AtlanticCounty, New Jersey. It is smaller than Lepadella latusinus (Hilgen-dorf)1 and has relatively shorter toes. The lateral angles of the posteriormargin are very acute; they never curve outward and forward as in theexuberant forms of Lepadella latusinus. This variety is constant. Speci-mens from Mount Desert Island and New Jersey were found to agreein all respects.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 761.Lepadella xenica, new speciesFigures 22, 23, 24The body is pyriform in outline, the greatest width being near the anterior margin,from whence it diminishes gradually, and is prolonged posteriorly as a bluntly pointedprojection. The body is shallow. A low elevation arises near the anterior marginof the dorsum, diminishing gradually in width and ending in a low flange. The lateraledges of the lorica overhang slightly. The dorsal sinus is fairly deep and surroundedby a prominent stippled collar, the beads of which are more strongly marked, with onepossible exception, than any other known species of the genus. The ventral sinus issomewhat greater in depth than the dorsal and is equally as well marked by a stippledcollar.'See Harring, 1916, Proc. U. S. Nat. Mus., LI, p. 542, PI. XCI, figs. 7-12.7AMERICAN MUSEUM NOVITATESThe foot groove is deep, quite narrow anteriorly and flaring posteriorly. Thefoot is relatively short and the terminal joint is somewhat longer than the combinedlength of the first and second joints. The toes are very long; they diminish graduallyto extremely slender, drawn-out tips.Length of lorica, 90,u; foot groove, 32,u; foot, 25MA; terminal foot joint, 12,;toes, 45,u. Width of lorica at widest part, 704i; anterior points, 35M. Depth of dorsalsinus, 15,g; ventral sinus, 21,u.Lepadella xenica was collected in Aunt Bettie Pond during thesummer of 1927. It bears some resemblance to Lepadella hyalina Smir-nov, but differs from that species by having a much deeper dorsal sinusand also in the general shape of the body, particularly the posteriorportion. It also somewhat resembles Lepadella myersi Edmondson. Itdiffers from that species by being much more shallow dorsoventrally;by having a deep V-shaped anterior dorsal sinus, instead of beingstraight; by having relatively much longer toes lying side by side, in-stead of the left being under the right; and by having a rounded posteriorprojection, instead of being squarely truncate posteriorly. In bothspecies the beaded stippling of the collar is very prominent.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 669.Lepadella visenda, new speciesFigures 25, 26, 27The body is moderate in depth and is subrhomboidal in outline. The dorsum isevenly arched. The anterior dorsal margin is slightly convex and no stippled collar ispresent. The ventral sinus is deep and roughly U-shaped; there is an inconspicuousline parallel to it marking the collar limit. The posterior margin of the dorsal plate isflaring and bounded laterally by prominent blunt points.The foot groove is deep, the anterior half narrow, the posterior half flaring.The terminal foot joint is about equal to the combined length of the first and secondjoints. The toes are long, the outer edges being straight; the inner edges are ex-panded at the base, then diminish gradually to form very slender tips.Length of lorica, 108,u; foot groove, 361A; foot, 22,u; terminal foot joint, 12,u;toes, 45,u. Width of lorica, 75/A; anterior points, 32gA. Depth of ventral sinus, 28,u.Lepadella visenda, while not common, is evenly distributed through-out the island. It has also been collected sparingly in Atlantic County,New Jersey. The species bears a certain resemblance to Lepadellalatusinus, but differs mainly in the very long slender toes, bulbous atthe base, and in the blunt lateral projections of the posterior. margin.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 668.8 [No. 76024272532Fig. 22. Lepadella xenica, dorsal view. Fig. 23. Ventral view. Fig. 24. Crosssection of body. Fig. 25. Lepadella visenda, dorsal view. Fig. 26. Ventral view.Fig. 27. Cross section of body. Fig. 28. Lepadella triptera, normal form, ventralview. Fig. 29. Mount Desert Island specimen, ventral view. Fig. 30. Karlsruhespecimen, ventral view. Fig. 31. Lepadella triptera var. alata, dorsal view. Fig. 32.Cross section of body. The figures of this- variety are on a smaller scale than those ofthe other species.9AMERICAN MUSEUM NOVITATESLepadella triptera var. alata, new varietyFigures 28, 29, 30, 31, 32Lepadella triptera Ehrenberg' is evidently quite variable. Thenormal form is constant in a circumscribed locality, and it is only whenmaterial from widely separated locations is brought together and com-pared that the different forms are seen to intergrade. The extreme ofsuch a series should be accorded varietal rank, and it seems that Lepa-della triptera var. alata is the extreme of the exuberant forms.Figure 28 shows the normal form. Figures 29, 30, and 31 show theoverlapping forms culminating in the winged variety, alata. Figures 28and 29 are reproduced from drawings kindly sent by H. Hauer who col-lected the specimens near Karlsruhe, Baden.Measurements of specimen shown in figure 8, material from Duck Brook, MountDesert Island, are: Length of lorica, 80,; foot groove, 25,u; foot, 20,u; terminal footjoint, 10,; toes, 15,u. Width of lorica, 72,u. Depth of ventral sinus, 20,u. Measure-ments of normal specimen: Length of lorica, 75,u; foot groove, 25ju; foot, 231A;terminal foot joint, 10,u; toes, 201c. Width of lorica, 64,u. Depth of ventral sinus, 14,s.The type is deposited in The American Museum of Natural History;Cat. No. A.M.N.H. 762.ADDITIONS TO THE MOUNT DESERT ISLAND FAUNAL LISTSince the faunal list of rotatorian species of Mount Desert Islandwas published in the American Museum Novitates (No. 494, September,1931), the following species have been added: Collotheca atrochoides(Wierzejski), Witch Hole, and Voronkovia mirabilis Fadeew, from TheTarn.BIBLIOGRAPHY(1) HARRING, H. K. 1916. 'A Revision of the Rotatorian Genera Lepadella andLophocharis with descriptions of five new species.' Proc. U. S. Nat.Mus., No. 2164, LI, pp. 527-568, PIS. LXXXIX-XCVII.(2) REMANE, A. 1929-1933. 'Rotatorien, Gastrotrichen und Kinorhynchen.'Bronn's 'M1. und Ordn. des Tierr.,' IV, Abt. II, Buch 1, Lief.1-4, pp. 1-576, Figs. 1-332.'See Harring, 1916, Proc. U. S. Nat. Mus., LI, p. 560, PI. xcv, figs. 1-4.10 [NoI. 760

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Rotifera on Mount Desert Island.

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