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Eight species of rodents are described based on previously unreported fossil material from the early Eocene Adobe Town Member of the Washakie Formation of Wyoming. Among these are two new species: the sciuravid Pauromys turnbulli and the cylindrodont Pareumys flynni. The overall rodent fauna consists of twelve species. The greatest change in the rodent fauna is between the lower and middle units of the Adobe Town Member; six species having their last occurrence in the lower unit and three species having their first occurrence in the middle unit. This coincides with the boundary of the Bridgerian and Uintan North American Land Mammal Ages.

Three species of Yoderimyinae (Eomyidae: Rodentia) are recognized from the lower part of the White River Formation (early to medial Chadronian) in the Flagstaff Rim area, Wyoming. The new material allows an improved diagnosis for the subfamily. The enamel microstructure of Yoderimyinae supports its inclusion in the Eomyidae.A new genus, Zemiodontomys, is established for Yoderimys burkei Black, and new material, including upper dentition, is referred to this species. This genus differs from Yoderimys in having higher crowned and more lophodont teeth and in lacking P3. A second new genus, Litoyoderimys, is established for Yoderimys lustrorum Wood, and a new species, L. auogoleus, is referred to the genus. This genus has lower crowned, more cuspate teeth than Yoderimys.Through early and medial Chadronian time, evolution in yoderimyines includes the following morphologic transformations: increase in size; increase in crown height and lophodonty of cheek teeth; reduction of P3 (from double-rooted, to single-rooted, to absent); increase in relative size of P4 and p4; and increased longitudinal torsion of the mandible.

Korth, William W., Robert J. Emry, Clint A. Boyd, and Jeff J. Person. Rodents (Mammalia) from Fitterer Ranch, Brule Formation (Oligocene), North Dakota. Smithsonian Contributions to Paleobiology, number 103, vi + 45 pages, 17 figures, 15 tables, 1 appendix, 2019.—Eighteen rodent species are recognized from the Fitterer Ranch fauna of North Dakota on the basis of more than a thousand collected specimens. Of the species recognized, four are new: the prosciurine aplodontiids Prosciurus hogansoni and Altasciurus leonardi, the heliscomyid Heliscomys borealis, and the cricetid Eumys lammersi. A previously described castorid from this fauna, Oligotheriomys primus Korth, 1998, is considered a synonym of “Eutypomys” magnus Wood, 1937, on the basis of the recovery of lower dentitions but is retained in the genus Oligotheriomys. A single specimen is questionably referred to Microparamys, a genus elsewhere limited to the Eocene (Clarkforkian-Chadronian land mammal ages). The rodent fauna appears to be a combination of predominantly Orellan and Whitneyan species (early Oligocene), suggesting that the section might transcend the Orellan-Whitneyan boundary. However, the rodent fauna does not alter significantly from the lowest to the highest horizons.

The White River Formation at Flagstaff Rim in central Wyoming is a key sequence for understanding the biochronology and chronostratigraphy of the Chadronian North American Land Mammal Age. The lower part of this section represents early Chadronian time, an interval whose fauna has not been well known. From these early Chadronian levels 15 species of rodents are discussed and/or described. Of these, three are new species, all belonging to the Eomyidae: Namatomys erythrus, Metanoiamys paradoxus, Cristadjidaumo skinneri. These rodent assemblages add substantially to our knowledge of early Chadronian faunas, and show successional changes in the rodent taxa from the earliest Chadronian through middle Chadronian.

Four species of rodents (two heteromyids and two cricetids) and one lagomorph are identified from the late Tertiary Sevier River Formation of Utah. The heteromyids include a new genus and species of heteromyine, Metaliomys sevierensis, which is intermediate in morphology between the Clarendonian and early Hemphillian Diprionomys Kellogg and the extant genera Liomys and Heteromys. A single specimen is referred to Diprionomys sp., cf. D. minimus (Kellogg). The cricetid Paronychomys lemredfieldi Jacobs is known from the Hemphillian of Arizona. The second cricetid is referred to a new genus Basirepomys. Peromyscus pliocenicus Wilson from the Hemphillian of California is designated as the type species of the new genus, to which the new species B. robertsi from Utah is referred. Basirepomys is viewed as intermediate between Peromyscus and the basal neotomyine Repomys May from the late Hemphillian and Blancan. The only lagomorph in the fauna is Hypolagus vetus (Kellogg). Four of the taxa recognized from...

Previously, it was believed that there was a dramatic turn-over in the fauna of beavers (Rodentia, Castoridae) from the Barstovian to the Clarendonian from Nebraska. Stratigraphically controlled collections of fossil castorids from the Valentine Formation, which cross this boundary, now indicate that a complete change in the castorid fauna did not occur, but instead a more gradual change and replacement of earlier taxa with more advanced taxa occurred. The range of Eucastor tortus and Monosaulax skinneri is extended from late Barstovian into the latest Barstovian Devil's Gulch Member and the range of the otherwise Clarendonian species of Prodipoides is extended downward into the late Barstovian Crookston Bridge Member. The skulls of Monosaulax skinneri and Eucastor valentinensis are described in detail for the first time. The cranial morphology of M. skinneri is primitive for Castoroidini and that of E. valentinensis is specialized for tooth-digging behavior as in the Nothodipoidini. A new genus, Temperocastor, is proposed for E. valentinensis based on its primitive morphology of the cheek teeth and derived cranial morphology. Temperocastor represents the most primitive nothodipoidine.

The skull and mandible ofNothodipoidesKorth are described. There are a number of adaptations present that are shared with other rodents with tooth-digging behavior (procumbent, elongated, and flattened incisors; anteriorly tilted occipital; strongly arched upper diastema). A new tribe of Castoroidinae, Nothodipoidini, is proposed forNothodipoidesandMicrodipoidesKorth and Stout, based on the fossorial adaptations of the skull, and their generally smaller size. It appears that fossorial adaptations have occurred in castorids at least three times: the Palaeocastorinae (Whitneyan through Arikareean), the primitive beaverMigmacastor(Arikareean), and the Nothodipoidini (late Barstovian through the Clarendonian).

A new genus of sciurid, Hesperopetes, contains three species: H. thoringtoni (type species), H. jamesi, and H. blacki. H. thoringtoni is from the early Chadronian (late Eocene) White River Formation of central Wyoming and represents the earliest recognized species of sciurid. The other species are from the latest Whitneyan or earliest Arikareean (late Oligocene) Blue Ash local fauna of South Dakota. Hesperopetes is closest in dental morphology to Oligopetes Heissig, which is known only from the early Oligocene of Europe. Hesperopetes may also represent the earliest occurrence of a lineage leading to pteromyine sciurids (“flying” squirrels). It is impossible at this time to construct a phylogeny of North American “flying” squirrels due to their scarcity in the fossil record and their undetermined relationships with Old World taxa.

Hopkins (2004) recently reviewed the species of Ansomys Qiu (1987). She recognized only two species from North America, A. nexodens (Korth, 1992) from the Orellan (early Oligocene) of Montana, and A. hepburnensis Hopkins (2004) from the Barstovian (middle Miocene), also of Montana. This left a considerable time gap between the known record of North American species, which led her to suggest a series of migration events between Eurasia and North America throughout the Tertiary. Recently, Kelly and Korth (2005) named an additional species of Ansomys, A. nevadensis from the Hemingfordian (early Miocene) of Nevada, thus partially filling the time gap between the previously described North American species. Kelly and Korth (2005), however, noted that A. nevadensis was morphologically closer to the Asian middle Miocene species A. orientalis Qiu (1987) rather than the other North American species. The fossil specimens described below are from the latest Whitneyan or earliest Arikareean of South Dakota (late Oligocene), once again, filling another time gap in the North American record of Ansomys. They also represent the easternmost occurrence of the genus in North America. Dental terminology used follows that of Wood and Wilson (1936) with modifications of Rensberger (1975). All specimens cited are part of the research collections at the Carnegie Museum of Natural History (CM).

A new species of squirrel, Sciurus olsoni, from the late Miocene (Clarendonian) of Nevada, is distinguished from other species of Sciurus by its smaller size and minor differences in the cheek teeth. It is the first Miocene record of the extant genus Sciurus, and the first record of a tree squirrel (tribe Sciurini) in North America between the early Miocene (Arikareean) and the Pleistocene. This late Miocene occurrence in North America suggests that the history of tree squirrels in North America was probably continuous through the Neogene, and the intermittent fossil record is due both to preservation bias and to their never having been abundant as living elements of fossil faunas; they are rare even where they do occur in deposits that are otherwise very richly fossiliferous. The later Tertiary and Pleistocene radiation of tree squirrels may have originated in North America.

Migmacastor procumbodens, gen. et sp. nov. is described from the late Arikareean of Nebraska based on a nearly complete skull. The new taxon exhibits various incisal specializations (e.g., incisors...

Scientific Committee on Antarctic Research (SCAR) The GPS campaigns of the between 1995 and 1998 provide a valuable data set which is used to link Antarctica with the ITRF (International Terrestrial Reference Frame), and to gain the first detailed insights into the tectonic behaviour of the Antarctic plate. The data analysis is based on seven individual solutions with four different software packages (Bernese, GAMIT/GLOBK, GIPSY/OASIS II, GEONAP), and provides the possibility to study the existing software noise. The combined solution yields an accuracy of 1 cm for the horizontal and 2 cm for the vertical coordinate components within ITRF96. Based on repeated observations during a total time span of three years, it is possible to determine detailed regional deformations in the area of the Antarctic Peninsula and to obtain an estimate for the rotation vector of the whole Antarctic plate. The main findings of a very comprehensive project of, in total, seven working groups are summarized and presented for the first time. The main emphasis is on the geodetic aspects of the project, i.e. the analysis of the same data set with different software packages, and on the final results from repeated observations, namely station coordinates and horizontal velocities in ITRF96.

The promylagaulines are represented in the late Hemingfordian to early Barstovian by a single genus, Galbreathia n. gen. Galbreathia is erected for the problematical Hemingfordian species Mylagaulus novellus Matthew. The early Barstovian species Trilaccogaulus bettae Sutton and Korth is included as a referred species. This genus is included in the generally primitive Promylagaulinae rather than the advanced Mylagaulinae because of the primitive condition of the skull (not as wide as long, single sagittal crest, more gracile appearance, occipital not anteriorly sloped) and skeleton (limb bones not as fossorially adapted), even though it has attained many of the derived features of the cheek teeth of Mylagaulinae (loss of P3, greater hypsodonty, loss of first molar with eruption of permanent premolars). Galbreathia is a derived promylagauline that shows parallel development of the dentition with the later, more specialized mylagaulines.

In the region of the Schirmacheroase (71 °S, 12°E) various geodetic and glaciological research activities have been carried out in the last decade. Several times three geodetic-glaciological traverses were undertaken to study ice velocity, accumulation and ablation, and ice surface height changes. Repeated ground surveys show a significant decrease in surface heights by about 15 cm/y for a large blue-ice area. This paper presents the first interferometrically derived ice velocity field of the inland ice close to the Schirmacheroase. The interferometric analysis of the synthetic aperture radar (SAR) data is performed in combination with ground-based information. Since only ERS-1&2 tandem mission image couples are available for this region a digital elevation model (DEM) is used to remove the effect of topography. Ice velocities up to 100 m/y are proved interferometrically for this part of the inland ice.

Two new species, Mojavemys galushai and Phelosaccomys neomexicanus, are described from the Barstovian of New Mexico. Both of these species are assigned to a new subfamily, the Mojavemyinae. It is uncertain as to whether this new subfamily should be referred to the Heteromyidae or Geomyidae.Both Mojavemys an Phelosaccomys retain some heteromyid characteristics while developing advanced traits of geomyids. It is possible that these genera represent transitional forms between a heteromyid ancestor and advanced geomyines, thus deriving the Geomyidae directly from the Heteromyidae sometime in the middle Tertiary. It is also possible that the Mojavemyinae are a subfamily of heteromyids only convergent with geomyids. A third possiblity is that the mojavemyines are among a group of middle Tertiary geomyoids from which both Recent heteromyids and geomyids were derived.

A new genus of mylagaluid rodent from the Miocene of the Great Basin, Hesperogaulus, is described, and to it two new species, H. gazini and H. wilsoni (type species) are referred. This genus differs from all other genera of later Tertiary mylagaulines in having: large bosses of rugose bone on the anterior end of the nasal bones; lower slope of the occipital bone; and unique separation of the anterior branches of the forked parafossette on the upper premolar.Hepserogaulus n. gen. represents a distinct lineage of mylagaulids that has been separate from other members of the family since the early Barstovian. This genus is geographically limited to the Great Basin. Other later Tertiary genera of mylagaulids show geographic limitations to other parts of the continent as well.

A nearly complete skull of Anchitheriomys from the Miocene of Nebraska allows description of the cranial foramina. In skull characters, Anchitheriomys most closely resembles Agnotocastor and Neatocastor among castorids; it retains primitive features that it shares with eutypomyids (position of the posterior palatine foramina, smooth palatal surface, nearly parallel tooth rows, retention of dP3) combined with derived features (elongate rostrum, procumbent incisors) that are shared only with Agnotocastor and Neatocastor. A new subfamily, Agnotocastorinae, is erected for this group of primitive beavers.

A new genus of eomyid, Metanoiamys, is described from the Uintan of southern California. Two new species, M. agorus and M. marinus are also named. All Eocene species previously referred to “Namatomys” are included in Metanoiamys. Species of Metanoiamys increase in crown height and lophodonty of the cheek teeth through time, though no species lineages are recognizable. Metanoiamys represents the stem genus for the Namatomyini and possibly Eomyinae, but not for the entire Eomyidae.

MARKS, E. 1950. Biostratigraphy of the Jonah quadrangle, Williamson County, Texas. Unpubl. M.A. thesis, University of Texas, Austin, 140 p. MEEK, F. B. 1876. A report on the invertebrate Cretaceous and Tertiary fossils of the Upper Missouri country. U.S. Geological Survey of the Territories, 9, 629 p. MILLER, H. W. 1968. Invertebrate fauna and environment of deposition of the Niobrara Formation (Cretaceous) of Kansas. Fort Hays Studies-New Series, Science Series, 8, 90 p. PESSAGNO, E. A., JR. 1969. Upper Cretaceous stratigraphy of the western Gulf Coast area of Mexico, Texas, and Arkansas. Geological Society of America, Memoir 111, 139 p. PRATT, L. M. 1984. Influence of paleoenvironmental factors on preservation of organic matter in middle Cretaceous Greenhorn Formation, Pueblo, Colorado. American Association of Petroleum Geologists Bulletin, 68:1146-1159. REESIDE, J. B., JR. 1957. Paleoecology of the Cretaceous seas of the Western Interior United States, p. 505-541. In H. S. Ladd (ed.), Treatise on Marine Ecology and Paleoecology, Volume 2, Paleoecology. Geological Society of America, Memoir 67. Scorr, G. R., AND W. A. COBBAN, 1964. Stratigraphy of the Niobrara Formation at Pueblo, Colorado. U. S. Geological Survey, Professional Paper 454-L, 30 p. , AND . 1986. Geologic, biostratigraphic, and structure map of the Pierre Shale between Loveland and Round Butte, Colorado. U. S. Geological Survey, Miscellaneous Investigations Series, Map 1-1700.

A new species of the extinct aplodontid genus Prosciurus is described from the Orellan (Oligocene) of North Dakota and Nebraska. The upper dentition of this species shares several features with the primitive Asian meniscomyine aplodontid Promeniscomys and is, therefore, believed to represent an ancestral type for later meniscomyine aplodontids.

All species of North American marsupials from the Chadronian through Hemingfordian are reviewed. Most North American species of didelphids previously referred toPeratheriumare allocated toHerpetotherium.Five species ofHerpetotheriumare recognized.The ChadronianPeratherium donahoeiHough is synonymized withHerpetotherium valens(Lambe). The Orellan speciesHerpetotherium stevensoniCope is resurrected and referred, along with the ChadronianPeratherium titanelixMatthew, to a new genus,Copedelphys.BothCopedelphysandHerpetotheriumcan be derived from known Duchesnean species ofPeratheriumfrom North America.Two genera of peradectids are recognized,NanodelphysMcGrew andDidelphidectesHough.Nanodelphys minutusis synonymized with“Herpetotherium” huntiCope and a second species ofNanodelphysis recognized from the Arikareean, though not named.

Mookomys(?) bodei Wilson, from the Arikareean of California, is referred to the genus Tenudomys Rensberger, and two species previously referred only questionably to this genus, T. dakotensis (MacDonald) and T. basilaris Korth are definitely assigned to this genus, based on the association of upper and lower dental elements of T. bodei. At present it is impossible to assign Tenudomys to a recognized geomyoid family, but several cranial features ally it more closely to the Heteromyidae and Geomyidae than other geomyoids.

Morphology of the four known skulls of the early Arikareean (late Oligocene) Hitonkala andersontau Macdonald indicates that this species is a member of the Florentiamyidae. Hitonkala lacks some of the derived characters of the skull present in the most-advanced florentiamyids such as Sanctimus and Florentiamys , but is more derived than the Whitneyan Kirkomys . Florentiamyids share a number of derived cranial features with the Heliscomyidae and are the immediate sister group of that family.

The extant beaver, Castor, has played an important role shaping landscapes and ecosystems in Eurasia and North America, yet the origins and early evolution of this lineage remain poorly understood. Here we use a geometric morphometric approach to help re-evaluate the phylogenetic affinities of a fossil skull from the Late Miocene of China. This specimen was originally considered Sinocastor, and later transferred to Castor. The aim of this study was to determine whether this form is an early member of Castor, or if it represents a lineage outside of Castor. The specimen was compared to 38 specimens of modern Castor (both C. canadensis and C. fiber) as well as fossil specimens of C. fiber (Pleistocene), C. californicus (Pliocene) and the early castorids Steneofiber eseri (early Miocene). The results show that the specimen falls outside the Castor morphospace and that compared to Castor, Sinocastor possesses a: 1) narrower post-orbital constriction, 2) anteroposteriorly shortened basioccipital depression, 3) shortened incisive foramen, 4) more posteriorly located palatine foramen, 5) longer rostrum, and 6) longer braincase. Also the specimen shows a much shallower basiocciptal depression than what is seen in living Castor, as well as prominently rooted molars. We conclude that Sinocastor is a valid genus. Given the prevalence of apparently primitive traits, Sinocastor might be a near relative of the lineage that gave rise to Castor, implying a possible Asiatic origin for Castor.

Additional specimens of the eomyid rodent Adjidaumo douglassi Burke from the early Arikareean (late Oligocene) Gering Formation in Nebraska imply an Arikareean (rather than Whitneyan) age for the Killdeer Formation of North Dakota, from which the holotype of this species was recovered. The new material also supports the allocation of this species to Leptodontomys, a genus previously known only from the Miocene. The Barstovian genus Pseudadjidaumo, and the North American Hemingfordian specimen referred to the otherwise European genus Eomys also are referred to Leptodontomys. These synonymies suggest a nearly continuous record for Leptodontomys from the Arikareean through the Hemphillian (late Oligocene to late Miocene). This genus belongs to the Adjidaumo-Paradjidaumo lineage of eomyids. The Eomyidae are a primitive family of generally small geomyoid rodents that range from the late-middle Eocene (Uintan) to late Miocene (Hemphillian) in North America, and as late as the Pleistocene in Europe. Their diversity was greatest in the early Oligocene (Fahlbusch, 1973, 1979), then diminished rapidly in North America, with only a few species existing through the Miocene. No lineages of eomyids previously have been traced from the Oligocene to the Miocene of North America; the majority of the Miocene species being morphologically quite distinct from the older species. The specimens discussed here provide the first record of one of the indigenous-North American Miocene genera of eomyids ex

The problematical rodent genus Cedromus Wilson, previously only known from the Orellan of the Great Plains, has been considered a sciurid by some authors and an aplodontid by others. An excellent collection of complete skulls with associated mandibles from Converse County, Wyoming, has provided evidence that this genus is a sciurid but that it represents a new subfamily distinguished from all other sciurids by a unique zygomasseteric structure that closely approaches myomorphy. A second genus, Oligospermophilus Korth, also from the Orellan of the Great Plains, is allocated to this subfamily.Additional and more complete cranial material of the primitive aplodontid Prosciurus indicates that sciurids and aplodontids share a common ancestry and should be included together at least within the same suborder Sciuromorpha.Three species of Cedromus are recognized, C. wardi Wilson, C. wilsoni n. sp., and Cedromus sp.; the latter extends the known temporal range of the genus into the Whitneyan.

Excellent material, including two partial skulls, of the geomyoid rodent Heliscomys is the basis for a new species (H. ostranderi), and allows the recognition of a new family, the Heliscomyidae, which includes Heliscomys Cope and Apletotomeus Reeder. Heliscomyidae, an early offshoot of the Geomyoidea, is not ancestral to any later geomyoids. Two lineages of Heliscomys are recognized, one distinguished by reduction in size and specialization of the premolars, and the other (which includes H. ostranderi) by enlargement of the premolars and development of stylar cusps on the upper molars.

A new species, Harrymys canadensis, referable to the Harrymyinae (Heteromyidae), is described from the Barstovian Wood Mountain Formation of Saskatchewan. The genus Stratimus Korth et al. is included in the heteromyid subfamily Harrymyinae. Harrymys canadensis is the youngest species of the subfamily and is more derived than Stratimus or the Hemingfordian species of Harrymys. The Harrymyinae may be derived from the latest Arikareean Proheteromys matthewi Wood.

We recently proposed the generic name Douglassia for a species of fossil squirrel (Sciuridae, Rodentia) from the latest Eocene of western North America (Emry and Korth, 1996). The species was originally Sciurus jeffersoni Douglass, 1901, but had subsequently been included by Black (1963) in his genus Protosciurus. The name Douglassia is preoccupied by, and a junior homonym of, the turritid mollusk genus Douglassia Bartsch, 1934. The name Douglassciurus is here proposed as a replacement name for Douglassia Emry and Korth, 1996. Like Sciurus, the gender is masculine. The name of the species therefore becomes the combination Douglassciurus jeffersoni (Douglass, 1901). Acknowledgments We thank Christian F. Kammerer for bringing this nomenclatural error to our attention. LITERATURE CITED

Orohippus proteros n. sp. is the earliest and most primitive species of Orohippus known. It was collected from the Lost Cabin Member of the Wind River Formation, along with a fauna which is clearly of early Eocene age. Known only from the type specimen, O. proteros is distinguished from all contemporary hyracotheriines by the presence of a small hypocone on P4. Orohippus proteros is more primitive than all other members of the genus and later hyracotheres in the small size of the P4 hypocone relative to the protocone and in the subtriangular shape of P4. Orohippus is viewed as a monophyletic taxon with O. proteros as the ancestral species.

Upper dentition of Protosciurus mengi Black, from the Orellan Brule Formation, Nebraska, is described for the first time. The zygomatic plate is tilted anterodorsally, showing the beginnings of sciuromorphy as in the Arikareean species of this genus. A new genus of sciurid, Oligospermophilus, is named for the species originally identified as ?Protosciurus douglassi (Korth), based on additional material including a skull and upper dentitions. The zygomasseteric structure of O. douglassi is unlike any previously described Tertiary sciurid. The range of O. douglassi is extended from the late Chadronian to the Whitneyan. Three distinct lineages of sciurids, distinguished on dental morphology and zygomasseteric structure, can be traced in the Oligocene in North America; they are represented by the genera Protosciurus, Oligospermophilus, and ?Protosciurus.

Seven species of aplodontid rodents are recognized from the Orellan, four from the Whitneyan, and one from both horizons of Nebraska. Three new genera are recognized, Epeiromys from the Orellan, Oropyctis from the Whitneyan, and Campestrallomys from both horizons. Three new Orellan species (Prosciurus parvus, Campestrallomys annectens, and Epeiromys spanius), two new Whitneyan species (Oropyctis pediasius and Campestrallomys siouxensis), and one new species from the late Orellan and early Whitneyan (Prosciurus magnus) are described. An indeterminate species of aplodontid from the Whitneyan is also recognized. Only a few lineages of aplodontids can be traced from the Orellan into later times. Campestrallomys, Downsimus, and Haplomys can be derived from Prosciurus. Oropyctis may represent an early ancestor of the Mylagaulidae, but this relationship is quite tenuous. The biostratigraphic occurrence of several species of aplodontids in Nebraska suggests that all species are not continuous throughout ...

The aplodontid, Pelycomys cf. P. placidus Galbreath, a new species of Pelycomys , and possibly a third species of this genus, are recognized from the Orellan of Nebraska. The upper dentition of Pelycomys is also decribed. The new species are morphologically distinct from previously known Orellan species from Colorado and Wyoming and represent a distinct lineage. The presence of these new species in the Great Plains indicates that aplodontids were more diverse than previously known, and that species may be geographically restricted during the middle Oligocene as has been previously shown for other families of Orellan rodents. The late Eocene rodent Spurimus is suggested as a possible direct ancestor of Pelycomys independent of Prosciurus .

Additional fossil material from the Valentine Formation in Knox and Brown Counties, Nebraska, has allowed for the recognition of three new species of rodents, a heteromyid (Perognathus brevidens), a geomyid (Parapliosaccomys annae), and a zapodid (Schaubeumys cartomylos). The specimens referred here to P. brevidens were previously identified as P. furlongi, those of S. cartomylos were identified as S. grangeri, and those of P. annae were previously recognized as Lignimus cf. L. hibbardi. It is evident that Lignimus Storer should be restricted to the type species L. montis, and the remainder of the species referred to this genus are referred to Parapliosaccomys Shotwell. Parapliosaccomys is recognized as the earliest member of the subfamily Geomyinae based on its dental morphology, which extends the range of this subfamily into the Barstovian. The fauna from Annie's Geese Cross Quarry (Knox County) is recognized as being late Barstovian based on comparison with the older Norden Bridge Quarry (Brown County).

All genera previously referred to the Manitshini are reviewed. Ischyrotomus Matthew is synonymized with Pseudotomus Cope, and the tribe Manitshini is restricted to this latter genus and the Chadronian Manitsha. Pseudotomus is represented by three Bridgerian species, four Uintan species, and one Duchesnean and Chadronian species. Quadratomus Korth is removed from the Manitshini and included in the Paramyini based on morphologic characters of the mandible and dentitions. The massive postcranial bones of Quadratomus are interpreted as convergent on those of the manitshines. In addition to the type species, two other species of Quadratomus are recognized, Q. sundelli (Eaton) from the later Bridgerian, and a new species, Q. grossus from the early Bridgerian. A massive postcranial skeleton evolved three times in Eocene ischyromyids, in the Manitshini (Pseudotomus), in the Paramyini (Quadratomus), and in the Pseudoparamyinae (Plesiarctomys).

r- Paramys compressidens Peterson, from the Uintan of Utah, has long been considered a member of the genus Ischyrotomus Matthew. A re-examination of the type and referred specimens of this species demonstrates that it does indeed belong in the genus Paramys and that several of the previously cited referred specimens can be allocated to other known species. Systematic relationships between the species of Paramys are analyzed. Recognizable morphoclines within this genus are increase in size and amount of crenulation of the enamel on the cheek teeth, and changes in the cross-sectional shape of the lower incisor. Several species previously considered as belonging to Paramys (P. simpsoni Korth, P. savagei Michaux, P. pourcyensis Michaux, P. ageiensis Michaux) may be referable elsewhere. Thisbemys Wood, Leptotomus Matthew, and Tapomys Wilson can be directly derived from the known species of Paramys. The origin of several other genera may possibly be found within Paramys, but no ancestral morphotype is currently known. Gidley referred this species to the genus Ischyrotomus Matthew (1910), an allocation that has been followed by all subsequent authors. Korth (1985, p. 145) synonymized Ischyrotomus with Pseudotomus Cope (1872) and excluded P. compressidens from Pseudotomus stating that the latter species was ". . . clearly re- ferable to Paramys," but he did not offer any explanation for this allocation. A re-examination of the known material referred to P. compressidens and of other rodents from the Uinta For- mation of Utah demonstrates that this species belongs in the genus Paramys and has permitted a study of the phylogenetic systematics of Paramys from both North America and Europe. Dental nomenclature used below is from Wood and Wilson

The Uintan Leptotomus mytonensis Wood is transferred to the genus Mytonomys Wood, and the Duchesnean Leptotomus kayi Burke is synonymized with M. robustus (Peterson). Thus, two species of Mytonomys...

Experimental atmospheres consisting of 3 to 12 ppM hydrocarbons and 0.25 to 2 ppM NO/sub x/ were irradiated (uv). Increase in hydrocarbon yielded greater NO/sub 2/ formation. A greater HC/NO/sub x/ ratio produced more oxidants. Eye irritation was greatest at 1 ppM NO/sub x/ and increasing HC.

Agnotocastor readingi n. sp., from the Orellan of Nebraska, is intermediate in size between the Chadronian A. galushai Emry from Wyoming and the Orellan A. coloradensis Wilson from Colorado. It differs slightly in dental and mandibular morphology from these latter species and cannot be transitional between them. The simplification of the dentition in A. readingi may indicate a position ancestral to the Whitneyan A. praetereadens Stirton from South Dakota.

1. Entgegen den FeststellungenFlemings, der durch 2-p-Aminobenzolsulfonamid-Pyridin selbst in Verdunnungen von 1∶64000 bei einer Einsaat von 10000 Pneumokokken eine so starke Bactericidie zu beobachten glaubte, das keine Koloniemehr in der Wrightschen Kammer aus-wuchs, zeigen meine Untersuchungen keine vermehrte Blutbactericidie bei den mit Eubasinum behandelten Versuchspersonen. 2. In Konzentrationen von 1∶1000 des Eubasinums im Blut, das nachtraglich zugesetzt wurde, konnte ebenfalls keinerlei Wirkung der Substanz nachgewiesen werden. 3. Bei den mit grosen Gaben behandelten Personen wurde eher eine Abnahme als eine Zunahme der Blutbactericidie beobachtet.