The species of Eumys Leidy, 1856, are reviewed. Six species are recognized and emended diagnoses are presented for the genus and all species. The enigmatic species, Coloradoeumys galbreathi Martin, 1980, is considered a new junior synonym of Eumys elegans Leidy, 1856; Coloradoeumys Martin, 1980, therefore becomes a new subjective synonym of Eumys Leidy, 1856. Additional specimens of Eumys cricetodontoides White, 1954, and Eumys parvidens Wood, 1937, are recognized and described. A new species, Eumys euryodus, from the Whitneyan of Nebraska is described. Size and proportional measurements of the molars, along with features of the occlusal morphology, are the major factors used to distinguish the species of Eumys.

A decapod crustacean fauna of Tierra del Fuego, Argentina, is documented from the middle Miocene Carmen Silva Formation and the early? Miocene Cerro Águila Conglomerate of the Cabo Domingo Group. Three new genera and five new species are named: Asthenognathus australensis, new species; Miotymolus quadratus, new genus and species; Mursia fuegiana, new species; Pharkidodes agele, new genus and species; and Tierrapilumnus edseli, new genus and species. Compilation of all described species of decapods from late Oligocene to early Pliocene exposures in 18 general localities in Patagonia, southern Argentina, and Chile documents two paleobiogeographic provinces, Argentine and Chilean. Coupled with evidence from the biogeographic patterns of associated mollusks, the faunas from Tierra del Fuego have been assigned to the Argentine Paleobiogeographic Province. Comparison of the distribution of Miocene decapods with that of extant decapods (Boschi 2000) leads to the conclusion that the thermal separation of South Atlantic and South Pacific water in the Miocene was more pronounced than today, so that there is no evidence of a discrete Magellanic Biogeographic Province characterizing the high southern latitude region during the Miocene.

Information is presented on the distribution, life histories, and larval feeding habits of three species of Tetanocera Duméril (T. bergi Steyskal, T. plumosa Loew, T. stricklandi Steyskal) that prey as larvae on pulmonate aquatic snails. Tetanocera bergi is widely distributed in the western United States and Canadian provinces, T. stricklandi is known only from Alberta, and T. plumosa has a transcontinental distribution. Larvae of all three species are general feeders and consume several taxa of aquatic snails.

An annotated checklist of the fleas of Maryland is presented. Previous records are reviewed and new records listed including four new state records and 40 new county distribution records. The new additions to the Maryland flea fauna are all in family Ctenophthalmidae: Catallagia borealis Ewing, 1929; Conorhinopsylla stanfordi Stewart, 1930; Epitedia cavernicola Traub, 1957; Tamiophila grandis (Rothschild, 1902). The number of flea species known to occur in Maryland is now 31.

Specimens previously identified as the Hemphillian cricetid Basirepomys pliocenicus (Wilson, 1937) (=Peromyscus pliocenicus Wilson, 1937) by Korth and De Blieux (2010) have been re-examined, and several distinct species are here recognized. Specimens from the early Hemphillian Rome fauna of Oregon are referred to a new, more primitive species of Basirepomys Korth and De Blieux, 2010, here named Basirepomys romensis, new species, which differs from other species of the genus in having lower-crowned cheek teeth and incomplete alternation of cusps on some molars. Specimens from the early Hemphillian Juniper Creek and Little Valley faunas of Oregon are referable to Paronychomys Jacobs, 1977, rather than Basirepomys, and represent a new species, Paronychomys shotwelli, which is distinguished from other species of the genus by its larger size and relatively longer lower third molar. A specimen previously referred to Peromyscus pliocenicus from the early Hemphillian of Kansas is referable to Paronychomys sp. Specimens identified as Peromyscus cf. pliocenicus from the late Hemphillian of California represent a new genus and species, Miotomodon mayi, which is distinguished from Basirepomys and Paronychomys by its higher-crowned cheek teeth, position of the ascending ramus on the mandible, and morphology of the mesoloph (-id) on the molars. Miotomodon is a probable ancestor for both Repomys May, 1981, and the Recent Neotomodon Merriam, 1898.