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The oribatid mite genusZachvatkinibates, found in littoral, forest canopy, and forest litter habitats, includes some species showing distinct sexual dimorphism in the octotaxic system of dermal glands, and others lacking this dimorphism. Three new species in this genus are described on the basis of adults, each of which shows species-specific sexual dimorphism:Z. nortonisp. nov.andZ. schatzisp. nov.from beach debris in British Columbia, Canada, andZ. shaldybinaesp. nov.from the littoral in eastern and northeastern Canada. We discuss the association of sexual dimorphism with the littoral habitat of species in this genus and, more generally, the expression of sexually dimorphic porose areas in Ceratozetoidea. We revise the diagnosis for the genusZachvatkinibatesand present a revised key for adults ofZachvatkinibatesspecies of North America north of Mexico.

Morphology, distribution, and habitat data are presented for three species of the oribatid mite genus Gymnodampia Jacot occurring in North America. A revised generic diagnosis is given and the type species Gymnodampia setata (Berlese) is redescribed based on topotypic material from Missouri. Immatures of G. setata are described and aspects of their biology are presented. Two new species from North America, G. jacotisp. nov. and G. lindquistisp. nov., are proposed and described on the basis of adults, and a key is given for North American species of Gymnodampia. The ameroid genera Cristamerus Hammer, from Pakistan and China, and Defectamerus Aoki, from Japan, Korea, and China, are considered junior synonyms of Gymnodampia, and G. conformis (Fujikawa) is considered a junior synonym of G. fusca (Fujikawa). Immatures of G. setata are apheredermous, but with a circular line of dehiscence, whereas known immatures of the superfamily Ameroidea are eupheredermous. Nonetheless, without convincing apomorphic traits linking Gymnodampia to any known apheredermous family of Brachypylina, we hypothesize that Gymnodampia has lost the eupheredermy characteristic of Ameroidea, and we place it in the family Ameridae on the basis of adult similarities.

Two new species of litter-inhabiting leptonetid spiders from Korea are described: Leptoneta namkungisp. nov. from Mt. Buyong, Chungcheongbuk-do, and Leptoneta kwangreungensissp. nov. from Kwangreung, Gyeonggi-do.

The term gerrymandering always evokes spirited partisan debate and political controversy. Yet, when we begin to scratch at the surface, we see that there is more to gerrymandering than debates about cartographical aesthetics. The issue goes directly to the heart of theories of democracy and representation and is replete with controversy, irony, and inconsistency.My key point is that resolving the gerrymandering issue is distinct from, and therefore may not result in, improving representation. This point is due to the fact that neither jurists nor scholars have been able to set forth a clear and consistent definition of representation.Terminology:The term gerrymander must be distinguished from redistricting. The latter is the process by which congressional and legislative district lines are redrawn in order to balance their populations in the wake of the decennial census. The former uses redistricting for partisan ends by dividing concentrations of voters to prevent their coalescing into a majority in a district, or by concentrating so many group members into a district that their electoral strength is diluted because the extra votes could have been used to help elect a sympathetic candidate elsewhere. It is this notion—the dilution of voting power as a result of partisan cartography—that has made the term gerrymander so controversial.

DAWSON, M. R., AND L. KRISHTALKA. 1984. Fossil history of the families of Recent mammals, p. 13. In S. Anderson and J. K. Jones (eds.), Orders and Families of Recent Mammals of the World. John Wiley and Sons, New York. FLEAGLE, J. G. 1988. Primate Adaptation and Evolution. Academic Press, New York, London, 486 p. GOTO, H. E. 1982. Animal Taxonomy. Edward Arnold, London, 60 p. HILL, J. E., AND J. D. SMITH. 1984. Bats: A Natural History. University of Texas Press, Austin, 243 p. PECZKIS, J. 1988. Predicting body-weight distribution of mammalian genera in families and orders. Journal of Theoretical Biology, 132: 509-510. RIDE, W. D. L. 1964. A review of the Australian fossil marsupials. Journal of the Royal Society of Western Australia, 47:97-131. ROMER, A. S. 1966. Vertebrate Paleontology. University of Chicago Press, Chicago, London, 468 p. SAVAGE, D. E., AND D. E. RUSSELL. 1983. Mammalian Paleofaunas of the World. Addison-Wesley, London, Amsterdam, 432 p. SIGNOR, P. W., III. 1985. Real and apparent trends in species richness through time, p. 129-151. In J. W. Valentine (ed.), Phanerozoic Diversity Patterns. Princeton University Press, Princeton, New Jersey. VAN VALEN, L. 1973. Are categories in different phyla comparable? Taxon, 22:333-373. . 1975. Group selection, sex, and fossils. Evolution, 29:87-94.

Two bilateral gynandromorphs, specimens of Hydrotaea meteorica (Linn.) (Muscidae) and Siphona hokkaidensis Mesnil (Tachinidae), are described and illustrated. Circumversion of male genital parts is thought to have been prevented by adjacent female genital elements. Study of essentially unrotated male genital halves of these specimens suggests that asymmetry of male sternite 6 in schizophorans results from asymmetrical development (as advocated by Emmert (1972) and Griffiths (1972)) and not as a consequence of slight rotation during circumversion (as advocated by Crampton (1942) and McAlpine (1981)). From study of genital fusion of male and female sclerites across midline, it is further suggested that sternite 6 + 7 in the above species is derived primarily from sternite 6, not from sternites 6 plus 7 as described in Calliphora vicina R.D. by Emmert (1972).

Larvae of Neoacarus occidentalis Cook, the first known larval Neoacaridae, are described, and host association and distributional data for the species are provided. A provisional diagnosis for the genus Neoacarus and remarks on possible phylogenetic affinities of Neoacaridae are presented based upon new knowledge of larval morphology.