New or Incompletely Known Species of Feltria from North America (Acarina: Feltriidae)

The genus Feltria has a widespread Holarctic distribution. A few species (Lundblad, 1941, 1969) have also been reported from northern Burma but this latter area. as far as its water mite fauna is concerned, might better be considered part of the southern border of the Palearctic, rather than a part of the Oriental Region. Previously. thirty apparently valid species and subspecies of Feltria were known from North America. The present paper describes nine additional forms and brings the total from the Nearctic area to 39, which is nearly identical with the number known from Europe. Most North American species are found in mountainous regions, but four are known from cold streams and springs in Michigan. The majority of Nearctic species are found associated with mosses and other matted aquatic plants, but twelve (including four described in this paper) are typically residents of the interstitial water associated with stream sand and gravel deposits. For reasons to be listed along with the description of Feltria testudo n. sp., the genus Azugofeltria is reduced to the rank of subgenus. The terminology used in describing musclt: attachment plates and glandularia of the dorsum follows that of Cook (1961). In presenting measurements, those of the holotype and allotype are given first. If a series of specimens is available, the range of variation is given in parentheses following the measurements of the primary types. Holotypes and allotypes will be deposited in the Field Museum of Natural History (Chicago)

North American Species of the Genus Axonopsis (Acarina: Aturidae: Axonopsinae)

(excerpt) Members of the genus Axonopsis have a broad zoogeographic distribution but are unreported from the Australian region and South America south of Colombia. Species occur in permanent standing waters and streams (including interstitial water). Representa- tives of four subgenera, Axonopsis s. s., Brachypodopsis, Paraxonopsis and Vicinaxonopsis, have been collected in North America, and a species of the closely related genus Erebaxonopsis is also known from interstitial waters in California. The only anomalous aspects of the distributional patterns are the apparent absence of Hexaxonopsis (which has a relatively widespread Palearctic range) and the stream (and interstitial) habitat of the North American species of the typical subgenus. The European species occurs only in lakes

North American Species of the Genus Hydrochoreutes (Acarina: Pionidae)

Excerpt: Members of the water mite genus Hydrochoreutes have a Holarctic distribution. They are found in lakes, ponds, and sluggish streams, but usually only in small numbers and therefore long series of specimens are difficult to obtain. Two species, ungulatus (Koch) and krameri Piersig, have a widespread range in Europe and Siberia and the latter species is also known from Algeria. Marshall (1937) reported ungulatus from Maine, Michigan, Wisconsin and California. However, the present author has seen no specimens from North America which can be assigned to the latter species and the illustrations in Marshall\u27s paper are definitely not those of ungulatus. Therefore. there are no authentic records of the latter species in the New World. Cook (1956) named a new species, intermedius, from North America. Both the description and illustrations are inadequate for the latter and it is treated along with four new species in this paper

Cohen-Macaulay graphs and face vectors of flag complexes

We introduce a construction on a flag complex that, by means of modifying the associated graph, generates a new flag complex whose $h$-factor is the face vector of the original complex. This construction yields a vertex-decomposable, hence Cohen-Macaulay, complex. From this we get a (non-numerical) characterisation of the face vectors of flag complexes and deduce also that the face vector of a flag complex is the $h$-vector of some vertex-decomposable flag complex. We conjecture that the converse of the latter is true and prove this, by means of an explicit construction, for $h$-vectors of Cohen-Macaulay flag complexes arising from bipartite graphs. We also give several new characterisations of bipartite graphs with Cohen-Macaulay or Buchsbaum independence complexes.Comment: 14 pages, 3 figures; major updat

Two New Species of Water Mites from Ohio

Author Institution: Wayne State University, Detroit, MichiganTwo new species of Hydracarina, Tiphys weaveri (Acarina: Pionidae) and Axonopsis ohioensis (Acarina: Axonopsidae), are described from Wayne County, Ohio. The former species inhabits temporary ponds; the latter was collected in a newly formed lake

New or Incompletely Known Species of Feltria from North America (Acarina: Feltriidae)

The genus Feltria has a widespread Holarctic distribution. A few species (Lundblad, 1941, 1969) have also been reported from northern Burma but this latter area. as far as its water mite fauna is concerned, might better be considered part of the southern border of the Palearctic, rather than a part of the Oriental Region. Previously. thirty apparently valid species and subspecies of Feltria were known from North America. The present paper describes nine additional forms and brings the total from the Nearctic area to 39, which is nearly identical with the number known from Europe. Most North American species are found in mountainous regions, but four are known from cold streams and springs in Michigan. The majority of Nearctic species are found associated with mosses and other matted aquatic plants, but twelve (including four described in this paper) are typically residents of the interstitial water associated with stream sand and gravel deposits. For reasons to be listed along with the description of Feltria testudo n. sp., the genus Azugofeltria is reduced to the rank of subgenus. The terminology used in describing musclt: attachment plates and glandularia of the dorsum follows that of Cook (1961). In presenting measurements, those of the holotype and allotype are given first. If a series of specimens is available, the range of variation is given in parentheses following the measurements of the primary types. Holotypes and allotypes will be deposited in the Field Museum of Natural History (Chicago)

A Note on Visualizing Response Transformations in Regression

A new graphical method for assessing parametric transformations of the response in linear regression is given. Simply regress the response variable Y on the predictors and find the fitted values. Then dynamically plot the transformed response Y(λ) against those fitted values by varying the transformation parameter λ until the plot is linear. The method can also be used to assess the success of numerical response transformation methods and to discover influential observations. Modifications using robust estimators can be used as well

Ground-based Discovery of Cepheids and Miras in M101

We have identified 4 Cepheids and 5 Miras using KPNO 4m BVRI images of an outer field in M101. The Cepheid and Mira periods range from 30 to 60 days and 350 to 800 days, respectively. We derive independent Cepheid and Mira distance moduli that agree within experimental uncertainties. We find a true distance modulus of 29.08 +- 0.13 mag.Comment: 28 pages, compressed uuencoded file contains 2 .ps files; finding chart not included, available via anonymous ftp at ftp://igpp.llnl.gov/pub/alves/m101_fig3.ps ; accepted for publication in A

Estimating the Social Welfare Effects of New Zealand Apple Imports

This paper provides a demonstration of how a comprehensive economic framework, which takes into account both the gains from trade and the costs of invasive species outbreaks, can inform decision-makers when making quarantine decisions. Using the theoretical framework developed in Cook and Fraser (2008) an empirical estimation is made of the economic welfare consequences for Australia of allowing quarantine-restricted trade in New Zealand apples to take place. The results suggest the returns to Australian society from importing New Zealand apples are likely to be negative. The price differential between the landed product with SPS measures in place and the autarkic price is insufficient to outweigh the increase in expected damage resulting from increased fire blight risk. As a consequence, this empirical analysis suggests the net benefits created by opening up this trade are marginal.International Relations/Trade,