174 



GENUS HALICHCERUS. 



GENERIC CHARACTERS Muzzle very deep, obliquely 

 truncated ; head very fiat ; molars of the upper jaw simple, 

 those of the lower with an obsolete tubercle before and be- 

 hind the principal one. 



THE GREY SEAL. 



Halichoerus Griseus. NILSSON. 



PLATE X. 



SPECIFIC CHARACTERS. Molars differ from those of 

 the Vitulina in the absence, at least in most of them, of any 

 small tubercle ; the posterior margin of the palate is di- 

 rectly transverse ; the palatal foramina on the palatal 

 bones. 



Halichoerus Griseus, Nils. Phoca Halichoerus, Thieneman. Ph. 

 Gryphus, Fab. Grey Seal, Bell. 



BEFORE leaving (he shores of the northern hemi- 



