1. The genera Lepidogrammitis Ching and Weatherbya Copel.are merged in Lemmaphyllum. Presl. The inconstancy of the characters on which these genera have been separated in discussed.2. The following new combinations are proposed: Lemmaphyllum accedens (Bl.)Donk (basinym, Polypodium accedens Bl.) and Lemmaphyllum sect. Phlebodiopsis (Moore) Donk (basinym, Pleopeltis sect. Phlebodiopsis Moore)

DONK, M. A.

REINWARDTIA

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1. The genera Lepidogrammitis Ching and Weatherbya Copel. are merged inLemmaphyllum. Presl. The inconstancy of the characters on which these genera havebeen separated in discussed.2. The following new combinations are proposed: Lemmaphyllum accedens (Bl.)Donk (basinym, Polypodium accedens Bl.) and Lemmaphyllum sect. Phlebodiopsis(Moore) Donk (basinym, Pleopeltis sect. Phlebodiopsis Moore)

M. A. DONK

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NOTES ON MALESIAN FERNS—I On the genus Lemmaphylluin Presl

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R B I N W A R D T I APublished by Herbarium Bogoriense, Kebun Raya IndonesiaVolume 2t Part 3, pp. 403-410 (1954)NOTES ON MALESIAN FERNS—IOn the genus Lemmaphyllum PreslM. A. DONK*SUMMARY1. The genera Lepidogramniitis Ching and Weatherbya Copel. are merged inLemmaphyllum Presl. The inconstancy of the characters on which these genera havebeen separated in discussed,2. The following new combinations are proposed: Lemmaphyllum. accedens (BI.)Donk (basinym, Pnlypodiwm uccedens Bl.) and Lemmaphylhim sect. Phlebodiupsin(Moore) Donk (basinym, Phapeltis sect. Phlebodiopsis Moore).HISTORICAL.—Lemmaphyllum was introduced by Presl (1849: 157)as a segregate from his previously published genus Drymoglossum Presl(1836: 277 pi. 10 fs. 5, 6). The latter group is based on two species ofwhich the second, "D. spatulatum Presl in Meyen herb.," represents theLemmaphyllum element, the first being Pteris piloselloides L., the unavoid-able type species (selected) of the name Drymoglossum. The originalspecies of Lemmaphyllum are two, (i) Lemmaphyllum spatulatum Presl(Drymoglossum spatulatum Presl nom. nud.), the one species previouslyincluded in Drymoglossum, and (ii) Drymoglossum carnosum (Wall.) exHook.The main character for separating the two genera Presl found in theposition of the coenosori, halfway between the midrib and the margin ofthe blade in Lemmaphyllum rather than close to the margin as in Dry-moglossum. This looks very much like a flimsy pretext for excessivesplitting, but with our present knowledge it may now be stated that it isan example of Presl's acuteness in setting apart unrelated groups thatlook superficially strongly alike.Lemmaphyllum was neither accepted as a genus by Fee (1850-52: 94)nor, of course, appreciated by Hooker (1864: 189); both authors mergedit again in Drymoglossum. Mettenius (1856: 28; "Lemaphyttum") regardedL. carnosum as part of Taenitis Sw. As usual, Hooker's example remaineddominant for a long time and, for instance, Diels (1899: 302) andChristensen (1906: xlvi) accepted his treatment.* Keeper of Herbarium Bogoriense, Kebun Raya Indonesia,— 403 —404 R E I N W A R D T I A [VOL. 2However, after Goebel (1926: 140-148 pi. 11 fs. 75-78) had alreadyconcluded that the two genera should be kept apart, Christensen (1929:44) re-established Lemmaphyllum and his well documentated opinion hashardly been questioned afterwards. As to the differentiating characters,the lack of stellate hairs suffices to differentiate Lemmaphyllum fromDrymoglossum with similar coenosori; and the presence of peltate scalesin the young sori will serve to distinguish it from most other genera ofPolypodiaceae se-nsu stricto with coenosori, except Hymenolepis Kaulf.(= Belvisia Mirbel) and Drymotaenhtm Makino, the former with a fertile,strongly contracted, apical portion of the frond ('spike'), the latter withuniform, linear fronds and immersed coenosori; in both the coenosori arecovered by the strongly revolute edges of the frond at least when im-mature, Drymoglossum belongs to a quite different set of genera to whichPyrrosia Mirbel also belongs, and Christensen's renewed separation ofLemmaphyllum from Drymoglossum is certainly well-founded.When re-establishing the genus, Christensen at the same time broad-ened its limits by including a small group of species of which Drymo-glossum abbreviatum Fee and Neurodium sinen.se Christ were the principalrepresentatives. This made necessary the subdivision of the genus intotwo sections, section Eulemmaphyllum C. Chr. and section Pseudovittar'iaC. Chr,, both with uniform fronds. This treatment, excellent as it was,has been improved by Ching (1933: 58), who transferred the second sectionto Lepisorus (J. Sm.) Ching. Section Pseudovittaria is intermediate be-tween Hymenolepis and Lepiso?ius rather than between Lemmaphyllum andHymenolepis and its inclusion in Lepisorus is perhaps the best dispositionof it when one retains the first pair of genera as distinct. On the other hand,Ching proceeded to include a small number of species, like Polypodiumdrymoglossoides Baker, with rather uniform fronds and distinct, roundCpolypodioid1) sori. For this new element the new section PseudolepisorvsChing was established. The incorporation of this group weakens two ofthe leading characters of Lemmaphyllum, viz., the dimorphous fronds andthe linear coenosori, but all the same the transfer is an improvement, inmy opinion.Afterwards Ching was not satisfied with his own disposition of thesespecies with round sori and introduced for them a special genus Lepido-grammitis Ching:"Lepidogrammi t i s Ching (Lemmaphyllum § Pseudolepisonm Ching) . [Type spe-c ies : ] L. drymoglossoides (Bak.) Ching (Polypodium Bak . ) . . . . Lepidogrammitisinter Lepiaorem et LemmaphyIIem medium tenens, soris prioris, habitu, venatio, ettextura foliis dimorphis vel subdimorphis potius LftmmupkyiU."'^Ching (1940: 258).1954] DONK: Notes on Malesian ferns—1 405Copeland does not commit himself as to Lepidogrammitis, which,except for fleetingly mentioning it under Lemmaphyllum, he does notplace definitely anywhere. Ching's species occur in south-eastern Asiarather than in Malesia, and when Copeland had to deal with two Malesianrepresentatives of Lepidogrammitis, he promptly established for them thenew genus Weatherbya Copel. These two species are Poly-podium accedensBl. (type species by original designation) and Polypodium damuenseRosenst. ("a very small, not very distinct New Guinea derivative"):" Weatherbya is clearly related to Pleopeltis, as shown by the paraphyses. . . .It is distinguished from Pleopeltis by habit, the peculiar dimorphism, position of thesorus on its vein, and the spores. The two genera have no area in common, not quitemeeting in Luzon."—Copeland (1948: 191 pi. S).It will be noticed that Copeland compared his genus with PleopeltisHumb. & Bonpl. ex Willd. This genus, as emended by him, contains (in-correctly, I believe) also Lepisorus which is the group he had in mind inconnection with Weatherbya. What the differences in habit are is notstated. The peculiar dimorphism he described as follows: "the sterileovate or lanceolate [fronds], obtuse, the fertile contracted about themiddle and thence attenuate" (no dimorphism mentioned for Lepisorus).The spores are "minutely reticulate-roughened" as against "smooth ornearly so" in Lepisorus. The sori are said to be situated on veinletsexcurrent from the lowest cross-veinlets (at the union of several veinletsin Lepisorus) ; this statement is contradicted for Weatherbya by theaccompanying plate, where the sori are correctly depicted on the lowestcross-veinlets themselves.There is no doubt that Weatherbya is congeneric with Polypodiumdrymoglossoides and related species (Lepidogrammitis). Taxonomicallythere is nothing really significant to separate the two and I do not hesitateto assign Lepidogrammitis, and consequently also Weatherbya, to Lemma-phyllum. Dr. R. E. Holttum (in litt.) has agreed with this conclusion whichwas already summarily stated in a book-review (Donk, 1948: 282).TYPIFICATION.—The type species of Lemmaphyllum, should be L.spatulatum rather than the other original species, L. carnosum. Lemma-phyllum spatulatum was the first element known to Presl and, moreover,it was the only species he knew through specimens! At the end of thedescription of L. carnosum he indicated "ex icone," which clearly showsthat he did not see specimens of it. I agree, therefore, with Copeland (1948:189) who selected L. spatulatum ("spathulatum") as the type species.These reasons will make it also clear why I reject Christensen's earlierselection (1006: xlvi) of Drymoglossum carnosum as the type species.406 R E I T J W A R D T I A [VOL. 2Later he himself left the question unsolved by indicating: "Type-species:L. spatulatum Pr. and L. carnosum (Wall.) Pr." (Christensen, 1929: 45).Ching (1940: 259) followed Christensen's selection of 1906.VENATION.—One of the most telling characters of Lemmaphyllum ashere understood (inclusive of Lepidogrammitis and Weatherbya) is in thevenation which represents a much more simple type than in the generaLepisorus and Hymenolepis with which it is now usually compared andwith which it appears closely related.The costa of the simple, entire blade is percurrent, almost reachingthe apex. The main veins are pinnately arranged and send off their firstveinlet rather far away from the costa while dividing more or less typicallydichotomously. The two opposite veinlets from two neighbouring mainveins unite into an arch setting off a rather large costal areole whichnearly always contains a free, recurrent veinlet: the latter is simple(generally bending towards the basis of the frond) or once branched andarising from the arch. Following the costal areoles are one to three morerows of areoles. Each of these rows consists of distinctly smaller andmore numerous areoles than the preceding one; mostly their areoles alsoinclude a single recurrent veinlet (sometimes arising from the lateralsides rather than from the outer side of the areole) or are devoid ofsuch veinlets, while the outer areoles may be incomplete or often lack arecurrent veinlet. The veins and veinlets are conform. Excellent drawingsof this type of venation are to be found in publications by Wu, Wong, &Pong (1932: textpl, 120, Drymoglossum microphyllum), Ogata (1981: pi.163, Drymoglossum carnosum, pi. 164, D. microphyllum, pi. 165, D. nobu-koanum, pi. 166, D. obovatum), and Copeland (1948: pi. 6, Weatherbyaaccedens). This peculiar type of venation is rare among the Polypodiaceaesensu stricto with clathhrate scales and occurs in this series in its mosttypical form only, as far I have noticed, in Colysis Presl and closelyrelated groups: it is especially to be encountered in the small members(with simple fronds) of Dendroglossa Presl emend. Copel. (inclusive ofMyuropteris C. Chr.)1 and in some of those that have larger and pinnatifidfronds, for instance, Campium laciniatum Copel. (1928: 354 /. 10) andcertain forms with narrow segments of the complex of Colysis ellipticum(Thunb.) Ching. If one compares the venation of Lemmaphyllum withChistensen's figure (1929: j)l, 10 f. 3) of Myuropteris cordata (Christ)C. Chr. and of Leptochilus minutulum Fee (Copeland, 1928: f. 3, Campiumminutulum), two of the above mentioned small, entire-bladed species of1 This genus should rathei- be fused with Colysis,1954} DONK: Notes on Malesian ferns—/ 407Dendroglossa, with Leptochilus-]ike fertile fronds, the striking resemblancewill at once be noticed.I am inclined to consider this resemblance as a case of 'convergence.'The venation of Dendroglossa (inclusive of Myuropteris) is readily under-standable as derived from the normal Colysis type of venation. Colysis andDendroglossa differ, for instance, by the lack of peltate scales in theyoung sori and in being terrestrial, and in a general way appear notclosely related to Lemmaphyllum. Outside Polypodiaceae with clathratescales, the same kind of venation is found in some of the species ofDrymoglossum.The type of venation in Lemmaphyllum is perhaps the one really im-portant character to separate it from Lepisorus. On the whole the differ-ences in this respect are very evident, but the situation becomes less clearin some members of Lepisorus with strongly simplified venation. Typicallythe type of venation in the latter genus is more complicated than inLemmaphyllum. The basic pattern in Lepisorus is the same as in suchspecies of Goniophlebium Presl sensu Copel. (Schellolepis J. Sm.) in whichonly the costal areoles are well developed, but the areoles, especially thecostal ones, are strongly subdivided into subareoles by accessory veinletsforming a network and among which are free veinlets variously directed(as is also the case in Phymatodes Presl) ; the meeting point of the'axillary,' (first, acroscopic) veinlet (so notable in Goniophlebiurn) witha number of accessory veinlets in the costal main areole is the seat of thepleiosorus in Lepisorus: thus a quite different situation from that foundin Lemmaphyllum.SORI.—One of the main features of the original species of Lemmaphyl-lum is the one linear and longitudinal eoenosorus on each side of themidrib. This character is not quite stable: almost every plentiful collectionmay proove this. Christensen (1920: 49) mentioned a collection ofLemmaphyllum carnosum with "fertile leaves about as broad as thesterile ones and the sori much interrupted, almost polypodioid, thus verymuch resembling Polypodium subrostratum." Some of the specimensreferred to L. mierophyllum "approach Polypodium drymoglossoides Bak.. . . so much that they can only be distinguished from it with difficulty.The leaves of these specimens . . . are partly subdimorphous; besidesthe typical spathulate fronds some others are found that are similar tothe sterile ones, though larger and ovate-oblong . . ., but fertile, the sorioften interrupted, sometimes fully polypodioid." (Christensen 1929: 47).Of L. mierophyllum var. obovatum (Harr.) C. Chr. a frond was depictedin every respect quite typical of 'Lepidogrammitis' (Christensen 1929: 47408 R E I N W A R D T I A [VOL. 2pi. 5 f. 3c). Wu, Wong, & Pong (1932: textpl. 120A) gave a drawing of aplant of this species in which all of the fertile fronds except one out of tenshow a more or less pronounced tendency to polypodioid sori. Ching mayalso be quoted on this matter:"The sori in L. microphyllum and Polypodium drymoglossoides are perhaps thebest illustration of unstability of [the eoenosori], for on a single frond are often foundcompletely fused sori on the top, half-fused ones in the middle and entirely distinctones at the base. Although the two species above referred to are placed by modernauthors in two distinct genera, nevertheless the identity of species is not withoutdifficulty, particularly, in the presence of ample material"—Ching (1933: 95).I have seen ample collections of nearly all the species involved andshare this view unconditionally.DIMORPHISM.—The dimorphism of the fronds in the original speciesof Lemmaphyttum is quite pronounced and expresses itself by the longerstipes and the narrower blades in fertile fronds. It is worthy of note thatwhere a tendency to breaking up of the eoenosori may be noticed thedimorphism becomes simultaneously effaced: the more truly polypodioidand the farther apart they are, the shorter the stalks and the broaderthe blades, the extremes at the other end of the series showing hardlyany dimorphism at all, at least not more than is usual in the truly poly-podioid series of species added by Ching (section PseudolepisorVrS = genusLepidogrammitis).In the species of section Pseudolepisoms dimorphism is not whollyabsent. As a rule the sori are restricted to the apical half (or a stillsmaller portion) of the blade and this fertile portion often shows a tenden-cy to elongate and contract. In this respect there is really no essentialdifference between Polypodium subrostratum and Polypodium accedens,the type species of Weatherbya, for which the partial dimorphism wasespecially emphasized by Copeland ("the fertile [fronds] contracted aboutthe middle and thence attenuate").CONCLUSION.—The extremely closely-knit relations of the species witheoenosori with those with round sori in rows was already duly recognizedby'Christensen. Without perhaps agreeing as to the theoretical (phylo-genetic) basis underlying his conclusions, one may well share his con-clusion that the species involved are intimately related indeed:"'As often mentioned above several of the species [of Lemmaphyllum], dealt withshow so close a resemblance to certain species of Polypodium sect. Lepisoms [ —Lcmmaphyllum sect. Pseudolepisonis] that it seems probable, that each is a recentderivative from its polypodioid mother-species or rather from an older form whichduring the course of evolution has been split up into one polypndioid and one "dry-moglossoid' daughter-species. Pairs of such sister-species are f. inst.;1954] DONK: Notes an Malesian ferns—I 409Polypodium drymoglo&soides — Lemm-aphylhtm microphylhon "P. sitbrostratum — L. carnosnm. . . — . . . ."—Christensen (1929: 71).The main point at issue in this note is not whether Lepidogrammitisand Weatherbya are congeneric—this is hardly doubtful—, but whetherthese two supposed genera may be fused with Lemmaphyllum. In thisconnection two pairs of characters were considered above: (i) more orless uniform (or not too strongly dimorphous), almost sessile frondsagainst clearly dimorphous fronds with slender stipes, and (ii) rows ofdistinct, round sori against coenosori. In both cases the conclusion hasbeen that neither of the two can possibly serve as a generic basis forseparation. Therefore, Lemmaphyllum, Lepidogrammitis, and Weatherbyaare united here.Accordingly, for the Malesian region the new name Lemmaphyllumaccedens (Bl.) Donk, comb. nov. (basinym, Polypodium accedens Bl., Enum.121. 1828) is proposed. For those who want to keep apart in specialgroups within one genus the species with a tendency to form more orless complete coenosori and those with strictly round sori, Lemmaphyllumsect. Pseudolepisorus Ching. should be replaced by Lemmaphyllum sect.Phlebodiopsis (Moore) Donk, comb, nov- (basinym, Pleopeltis sect. Phlebo-diopsis Moore, Index Filicum lxxvii, 1857). The original species of Moore'ssection form a heterogeneous lot, but Christensen (1906: 1) maintainedit as a distinct group of Polypodium sect. Pleopeltis (Humb. & Bonpl.ex Willd.) C. Chr. and indicated Polypodium accedem, one of the originalspecies, as the type (or else as the only example of a typical species),excluding at least most of the others.BIBLIOGRAPHYCHING, R. C. (1933): The studies of Chinese ferns IX, In Bull. Fan mem. Inst. Biol. 4.(1940:) On natural classification of the family " Polypodiaecae." In Sun-yatsenia 5.CHRISTENSEN, C. (1906): Index Filicum . . . . Hafniae.(1929): Taxonomic fern-studies I I I . hi Dansk bot. Ark. 6 (3).COPELAKD, E. B. (1928) : Leptochilus and genera confused with it. In Philipp. J. Sci 37-(1947) : Genera Filicum. The genera of ferns. Waltham, Mass.DiELS, L. (1899): Polypodiaceae [in par t ] . In Engl. & Pr., Nat. PflFam, 1 (Abt. 4).DONK, M. A. (1948) : [Boekbespreking van] Genera Filicum , . . by E. B. Copeland . . .In Chron. Nat., Batavia 105: 281-282.FeE, A. L. A. (1850-52) : Genera Filicum. Exposition des genres de la famille desPolypodiacees {classe des fougeres). (Cinquieme memoire sur la famille desfougeres.) Paris & Strasbourg.GOEBEL, K. (1926) : IX. Beitrage sur Kenntnis der VerwantschafsverhaltnisBe einiget"javanischer Fame. [C. Drymoglossum.] In Ann. Jard. bot- Buitenzorg 36.41© R E I N W A R D T I A [VOL. 2HOOKER, W.J. (18(54): Species Fiiicum; . . .. Vol. V. 1864.METTENIUS, G. (1856): Filices horti botanici lipsiensis. Die Fame des BotanischenGartens zu Leipzig. Leipzig.OGATA, M. (1931): Icones Fiiicum Japoniae. Vol. IV. Tokyo.PREPL, C. B, (1836) : Tentamen pteridographiae seu genera Filicarum praesentim juxtavenarum decursum et distributionem exposita. Pragae.(1849): Epimeliae botanicae. Pragae.Wu, Y. C, K. K. WONG, & S. M. POKG (1932): Polypodiaceae yaoHhanensis, Kwangsi.In Bull. Dept Biol. Coll. Sci, Sun Yatssn Univ. No. S.

NOTES ON MALESIAN FERNS-I On the genus Lemmaphylluin Presl

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NOTES ON MALESIAN FERNS-I On the genus Lemmaphylluin Presl

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