THE COMMON SEAL AND THE GREENLAND SEAL 725 



r'" 

 landing, the animal will swim back and forth several times with head raised, and 



eye, ear, and nose on the alert to detect any sign of danger, the wary nature of the 

 creature being well shown by the fact that almost immediately after emerging from 

 the water the animal turns completely round so as to lie with the head seaward, and 

 in readiness for an instant dive. The fairer the day and the lighter the breeze the 

 more readily the seals come ashore, while during rough weather they not only do 

 not land so often but are more watchful when they do come out." This species is 

 less docile and intelligent than the common seal, and cannot be tamed in the same 

 manner. A specimen measuring eight feet in length weighed nearly four hundred 

 pounds. 



THE COMMON SEAL AND THE GREENLAND SEAL 

 Genus Phoca 



The common seal (Phoca vitulina] and the Greenland seal (P. grcenlandica) 

 may be selected as well-known examples of the genus Phoca, which is the only 



SKELETON OF THE COMMON SEAL. 



genus in the family containing more than two species. All the members of this 

 genus differ from the gray seal by their smaller and more-pointed teeth, but more 

 especially by the circumstance that each of the cheek-teeth, with the exception of 

 the first in each jaw, is implanted by two distinct roots, and has its crown composed 

 of three or four compressed cusps arranged in a line. In such a tooth there is one 

 large main cusp in the middle, which corresponds to the single cusp of the teeth of 

 the gray seal ; while in front and behind this are one or two much smaller cusps. 



The common seal, which is the only species in addition to the gray 

 seal ordinarily met with on the coasts of the British Islands, is one of 

 three nearly-allied forms, which, in the young condition, cannot always be satisfac- 

 torily distinguished from one another by color alone. The three species in question 

 are the common seal, the ringed seal (P. hispida), and the Greenland seal. All 

 these three species are much smaller than the gray seal; the ringed seal being the 

 smallest of all. The latter species can always be distinguished from either of the 

 others by the greater length of the first digit in the fore-foot, which exceeds that of 



