632 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



the immature deatition, and suggesting that such was probably also the 

 case with the corresponding section of Sorex with 30 teeth. Bat these 

 sections are perfectly valid, and to them I add a third, in Sorex, of 28 

 teeth. In 1875, Ur. Gill* elaborately reviewed the Insectivorous Mam- 

 mals atlarge, and proposed, mainly upon the basis of St. George Mivart's t 

 investigations, verified by original examination of much material, a class- 

 ification of the order believed to be the best yet presented. This valuable 

 article is especially full in its treatment of the two North American fam- 

 ilies, Talpidce and 8oricidce, and gives an extensive bibliography, but 

 scarcely touches upon the characters of the genera and species. 



Among other points may be mentioned the determination, by Pro- 

 fessor Verrill,! of the Sorex palustris of Eichardson as a valid species of 

 Neosorex; and the identification by Hr. Peters § of the Scalojis latimanus 

 of Bachman with ;S^. towmenrli of same author. 



The most noteworthy laborer in this field before 1857 was Dr. Bach- 

 man, whose results, however, required much remodeling. The determi- 

 nation of his Sorex fimbripes was made by Professor Baird in 1861 from 

 examination of the type, but is now first published in this paper. 



§ l.^THE AMERICAN GENERA OF TALPID.^. 



America furnishes four good genera of Moles, namely, Scaops, S a 

 panus^ Condylura, a>nd UrotricJius. The last-named belongs to a special 

 subfamily, llyogalince, i^rimarily distinguished from the Talpmce by the 

 characters of the scapular arch and fore limb. It is related to the Des- 

 mans of the Old World, and is the only known insectivorous genus com- 

 mon to both hemispheres, furnishing one of the many evidences of a 

 relation between the faunas of Western Narth America and Asia closer 

 than that subsisting between Eastern North America and Europe* 

 Scalops and Condylura, remarkable genera peculiar to America, have 

 been recognized almost from the first; but the very strong claims of 

 Scapanus to full generic rank have not been generally conceded. The 

 genus differs so widely in dentition from Soalops that it would accord 

 more closely with modern valuation of generic characters to give it full 

 rank and subdivide it into two subgenera for the accommodation of it 

 two remarkably distinct species, than to force it under Scalops, from 

 whi h it differs more than some of the Old World genera do from each 



* Synopsis of Insectivorous Mamma . < Bull. U. S. Geol. and Geogr. Surv., 2(1 ser., 

 No. 2, pp. 91-120. May 14, 187.5. 



+ Notes on the Osteology of the Insectivora. < Journ. Anat. and Phys., i, 1867, pp. 

 281-312 ; ii, pp. 117-154. (French translation : Notes snr FOst^ologie des Insectivores. . . 

 < Ann. Sc. Nat., 5es6r., zool. et pal6ont., viii, 1867, pp. 221-284 ; ix, 1868, pp. 311-372.) 



On Hemicentetes, a new genus of lusectivora, with some additional remarks on the 

 osteology of that order. < Proc. Zool. Soc. Lond., 1871, pp. 58-79, pi. v. 



X Proc. Bost. Soc. Nat. Hist., is, 1862, pp. 164-172, 225, 226. The same determina- 

 tion had been made by Baird in 1861 (MS. ined.). 



§ Monatsb. Konig. Preuss. Akad. Wissensch. Berlin, 1863, p. 656. 



