CALLORHINUS URSINUS NORTHERN FUR SEAL. 313 



figures. In all, the interorbital region is relatively broad and 

 short, and becomes relatively more and more narrowed and 

 lengthened in the adult. In young specimens, and always in 

 the females, except in Arctocephalus, the mastoid i^rocesses re- 

 main almost wholly undeveloped. Among the North American 

 species, JEiimetopias is easily recognized at any age by its dental 

 formula and large size. The young and females of Callorhinus 

 and Zalophus are easily separated, aside from dilferences of den- 

 tition, by the shape of the muzzle, but especially by the ascend- 

 ing limb of the intermaxillary. In Zalophus it gradually nar- 

 rows posteriorly and ends in a slender point near the middle of 

 the nasals. In Callorhinus it widens posteriorly and ends ab- 

 ruptly quite near the anterior border of the nasals. 



The distribution of the genus is almost exactly the same as 

 that of Uumetopias, namely, the shores of the North Pacific, 

 and, like that genus, is represented by only a single species, 

 the well-known Alaskan " Fur Seal." 



CALLOEHINUS UESINUS, {Linne) Gray. 



Northern Fur Seal; Sea-Bear. 



Ursus marinus, Steller, Nov. Comm. Acad. Petrop.,ii, 1751, 331, pi. xv. 



Phocaursiva, Linne, Syst.Nat., i,1758, 37 (from Steller). Scheeber, Sihigth., 

 ill, 1758, 289. Shaw, Gen. Zool., i, 1800, 2^5, pi. Ixii. Godman, 

 Amer. Nat. Hist., 1, 1826, 346 (in part). Fischer, Synop. Mam., 

 1829, 231. Pallas, Zoog. Rosso-Asiat., i, 1831, 102. 



Otaria ursina, Pieron, Voy. Terr. Austr., ii, 1816, 39, 41. DesmaRest, Nouv. 

 Diet. Hist. Nat., XXV, 1817, 595 ; Mam., i, 1820, 249. Harlan, Faun. 

 Amer., 1825, 112. Gray, Griffith's Cuvier's An. Kingd., v, 1829, 

 182. Hamilton, Marine Amphib., 1839, 253, pi. xxi. NiLSSON, 

 Arch. f. Naturg., 1841, 331 (in part only). MiJLLER, Arch. f. Naturg., 

 1841, 333. Wagner, Schreber's Saugt., vii, 1846, 65 (in part only) ; 

 Arch. f. Naturg., 1849, 39. VoN Schrenck, Amur-Lande, i, 1859, 

 189. 



Phoca (Otaria) ursina, Richardson, Zool. Beechey's Voy., 1839, 6. 



Otaria ( Callorhinus) iirsinus, Peters, Monatsb. Akad. Berlin, 1866, 373, 672. 



Arctocephalus ursimis, Lesson, Man. de Mam., 1827, 203. Gray, Cat. Seals, 

 1850, 41 (not of F. Cuvier, or only in part) ; Prgc. Zool. Soc. Lond., 

 1859, 103, 107, pi. Ixxiii (skull). Gill, Proc. Essex Institute, v, 

 1S66, 13. Scott, Mam. Recent and Extinct, 1873, 8. Clark, Proc. 

 Zool. Soc. Loud., 1878, 271, j)l. xx (colored figures of male, female, 

 and young). 



Callorhinus ursimis, Gray, Proc. Zool. Soc. Lond., 1859, 359, pi. Iviii (skull) ; 

 Cat. Seals and Whales, 1866, 44, fig. 16 (skull) ; Ann. and Mag. Nat. 

 Hist., 3d ser., xviii, 1866, 234 ; Suppl. Cat. Seals and Whales, 1871, 15 ; 

 Hand-List Seals, etc., 1874, 32, pi. xix (skull). Allen, Bull. Mus. 

 Comp. Zool., ii, 73, pU. ii, iii (skuil, etc.). Scammon, Marine 

 Mamm., 1874, 141, pi. xxi, figg. 1, 2, andtigg. 1-6 in text (animal). 

 Elliott, Cond. Affairs in Alaska, 1874, 123. 



