6 PHOCIBiE. 



tt Lower jaw strong, mth an acute angle; orbits moderate. 



4. Stbnobhynchus. Skull and muzzle elongate ; grinders compressed, 



with three cylindrical elongated lobes, the centre one longest and 

 largest. 



5. MoNACHUS. Skull broad, depressed behind ; muzzle short, broad ; 



orbits large ; grinders small, conical, thick, with a small anterior and 

 posterior lobe; lower jaw broad, with a distinct posterior angle; 

 upper cutting-teeth transversely notched ; palate ang^arly notched 

 behind. 



b. Ottftmg-teeth | ; the first grinder in each jaw single-rooted, the rest 



two-rooted; mtizzle bald, callous between and above the nostrils, and 

 divided by a central groove ; wrist rather exserted; jmgers suhequal; 

 claws five, large. Phocina. 



* Branches of lower jaw diverging; lower edge of lower jaw rmmded, 



simple; palate angularly arched behind; angle of lower jaw blunt, 

 sloping behind. 



6. Callocephalus. Muzzle rather narrow ; whiskers waved ; toes gra- 



dually shorter ; web between the hind toes hairy ; hair subcylindrical ; 

 under-fur thin. 



** Branches of lower jaw diverging; lower edge of lower jaw dilated on 

 the inner side. 



7. Pagomts. Palate angularly notched behind; angle of lower jaw 



blunt, sloping behind. 



8. Pagophilus. Palate truncated behind; angle of lower jaw acute, 



erect behind, with a notch above the basal tubercle ; muzzle rather 

 produced ; whiskers waved ; toes gradvially shorter ; web between 

 hind toes baidish ; hair diy, flat, close-pressed, without any nnder- 

 fur. 



*** Branches of lower jaw arched on the side and vnde apart; lower edge 

 produced on the inner side behind the syrriphysis; palate arched. 



9. fiALiCYON. Tubercle on inner edge of front part of lower jaw elon- 



gate, sharp-edged ; teeth moderate ; angle of lower jaw simple, with 

 a distinct notch above it. 



10. Phoca. Tubercle on inner edge of front part of lower jaw blimt, 

 rugulose; teeth small; angle of lower jaw with a rounded lobe on 

 inner side above the basal tubercle ; muzzle broad, short ; forehead 

 convex ; whiskers smooth, sirnple ; ear-hole large ; fingers unequal, 

 the third longest, second and forath long, the first and fifth shorter, 

 nearly equal. 



B. Grinders with single root (except the two hinder grinders of Hali- 

 choerus). 



c. Ears without any conch; toes simple, of fore feet exserted, of hind feet 



large, the inner and outer ones large and tang, the three middle ones 

 shorter; palm and soles hairy, sometimes chaffy and callous from 

 wear ; muffle hairy to the edge and between the nostrils. 



* Muzzle large, truncated, simple; canines large; grinders lobed, ivhen 



old truncated. Trichechina. 



11. Halichcbbtjs. Muzzle broad, rounded; cutting-teeth f ; grinders—, 



conical, the two hinder of the upper and hinder one of the lower iaw 



