12 GILL, PRODEOME OP A 



developed as tusks. Molars in young f ; the fifth and 

 fourth caducous. Anterior feet about as large as posterior, 

 with the toes decreasing in a curved line, destitute of 

 claws ; the posterior feet with the five digits, scarcely in- 

 creasing toward inner, all provided with claws. Scapula 

 with the hinder margin nearly straight, and the spine a 

 short distance from, and somewhat parallel with it. 



* One genus. ROSMAKUS. 



APPENDIX. 



For the benefit of American naturalists, a list of the 

 species of Seals inhabiting both coasts of North America, 

 is here given. I may add that I have seen more or less 

 numerous specimens of every species enumerated. 



Pinnipedes of Eastern North America. 

 PHOCIDJ3. 



PHOCIN^J. 



1. Phoca vitulina Linnaeus. Greenland to New York. 



2. Pagomys fcetidus Gray. Greenland to Labrador.* 



3. Pagophilus grcelandicus Gray. Greenland to 



Gulf of St. Lawrence. 



4. Erignathus barbatus Gill. Greenland to Gulf of 



St. Lawrence. 



5. Halichosrus grypus Nilsson.f Sable Island. 



* The Phoca fcetida and P. hispida appear to simply represent condi- 

 tions of a single species exhibiting a remarkable variation in dentition. 

 An examination of numerous specimens, differing in the number of the 

 cusps, forbids my considering such variations as constant and indicative of 

 specific value. They surely cannot be generically separated as Dr. Gray has 

 done. 



t The American form of Halichcerua differs somewhat from any of the 

 three forms signalized by Hornschuch, but the names of that gentleman 

 have not been regarded by others as the expression of valid species, and do 

 not really appear to merit recognition. I have therefore, provisionally at 

 least, identified the American type with the European, combining all the 

 known forms of the genus under one specific name. 



