558 FAMILY PHOCIDJE. 



ula, and in lacking the abrupt eversion of the upper border of 

 the ilia. 



The subgenus Phoca, consisting, so far as certainly known, of 

 a single species (Phoca vitulina), differs from Pusa (=Pagomys, 

 Gray), and from Pagophilus, principally in its generally heavy 

 structure, especially of the skull and dentition, and in the thick- 

 ness of the body and the shortness of the limbs, particularly of 

 the tibial and radial segments. Tn Pusa and Pagophilus the skull 

 is similar in general outlines and proportions, it differing in both 

 from Phoca in its generally much slighter structure, very small 

 teeth, flatness of the dorsal aspect of the brain-case, and the slen- 

 derness of the muzzle and whole facial region, as well as in the 

 form of the lower jaw. PagopMlus differs from Pusa in having 

 the posterior nares completely divided into two distinct pas- 

 sages, by the complete ossification of the narial septum, in the 

 broad form of the scapula, and in having only three, instead of 

 four, anchylosed sacral vertebrae characters possibly of generic 

 rather than subgeneric value. The well-known representatives 

 of these groups are respectively Phoca foetida and P. grcenland- 

 ica, to which are to be referred also the Phoca caspica and the 

 Phoca sibirica.* 



As already noticed (antea, p. 417) the name Phoca , by strict 

 adherence to rules of nomenclature, should be reserved for the 

 Phoca leonina, Linne", this being the only Linnean species of 

 Phoca left after the removal (in 1824) of Phoca vitulina as the 

 type of F. Ouvier's genus Gallocephalus. t Pusa of Scopoli, 1777, 

 with Phoca foetida as the type, however, long antedates Gallo- 

 cephalusj and would be strictly the name of the group were 

 Phoca set aside. Tet as Pusa may be deemed by some as unten- 

 able, and as to restrict PJwca, on, at best, a slight technicality, 

 to what is now called Macrorhinus, would be to subvert all the 

 traditions of nomenclature relating to the generic name of our 

 smaller Phocids, it seems best not to attempt, on so slight a 

 pretext, a change in nomenclature that would doubtless be re- 

 ceived with reluctance, if indeed it could be for a long time 

 brought into general use. 



Gallocephalus has been in more or less general use for the 

 smaller Phocids ever since it was proposed by F. Guvier in 

 1824, especially among the earlier French writers, and it has 



* If the Phoca nummularis of Temminck prove to be a valid species its 

 closest affinities are doubtless with P. mtulina. On this point see infra. 



tin the same paper, but eight pages later, Phoca leonina, Linn6, was made 

 the type of the same author's genus Macrorhinus. 



