TECHNICAL HISTORY SPECIES. 421 



Histriophoca, Pusa, Monachus, Cystophora, MacrorMnus, Lohodon, 

 Ogmorhinus, Leptonychotcs, and Ommatophoca. AVliile Dr. Gill 

 recoguized the same number of genera in 1877 as in 1866, the 

 nomenclature is quite different ; but this is due mainly to simply 

 changes of names, as the substitution of Pusa for Halichcerus, 

 of OgmorMnus for Stoiorhynchus, and of Leptonychotes for Lep- 

 tonyx; but in the later enumeration Pagomya is omitted and His- 

 trioplioca is added. 



So far as the number of genera is concerned, tlie greatest differ- 

 ence of oiiinion has always obtained in respect to the Pliocincc^ 

 all the members of which groui) are confined to the ]S"orthern 

 Hemisphere. Gray, after 1801 (1861-1874), uniformly recog- 

 nized seven ; Gill, 1866-1877, six, only two of which {Halichce- 

 rus and 3Tonac]ius, about which authors generally have for many 

 years been in unison) were the exact equivalents of Gray's 

 genera; but the chief disagreement consisted in Gill's use of 

 Phoca for what Gray termed Callocephalus, and of Urignafhns for 

 what Gray termed Phoca. Lilljeborg*, in 1874, referred all of 

 the species of the Phocinw, except Halicha^rus grypus (and Mo- 

 nachns alhiventer, which latter is not there treated), to the genus 

 Phoca, and von Heuglin the same year did the same, except that 

 Pagomys, Pagophilus, and CaUocephaJus (the latter being applied 

 to C. harhata) were recognized as subgenera under Phoca. The 

 classification and nomenclature of Giebel (1855), Blasius (1857), 

 Malmgren (1863), and Holmgren (1865) are, generically, the 

 same as Lilljeborg's in 1874. The tendency has, in short, been 

 to refer all the species of Phocinw, with the two exceptions al- 

 ready specified, to the Linntean genus Phoca. 



Species. Although Seals have figured in works on natural 

 history since the time of Rondelet, Olaus Magnus, and Gesner - , 

 (1554-1555), it is unnecessary in the present connection to refer ] 

 in detail to those earlier works, since down to the time of Steller % 

 (1751), all the Phocids or Earless Seals known to systematic 

 writers were referred to the common Seal {Phoca vitulina, auct.) 

 of the shores of Middle and Northern Europe. This indeed was 

 the only species recognized by Linne, from the Northern Hem- 

 isphere, even in the last (1766) edition of his "Systema Naturse." 

 But other species had been incidentally and vaguely described 

 by the early Greenland missionaries, and by exjilorers and trav- 

 ellers in both the Arctic and Antarctic regions, to which refer- 



* Fauna Sveriges och Norges Eyggraclsdjur, i, Diiggdjnren, pp. 667-729. 



