On the Phocidee of the Greenland Seas. 393 



bluish colour on the back, while on the breast and belly it 

 is of a dark silvery hue. 



Young seals retain this appearance throughout the sum- 

 mer, and are termed " blue-backs/' The next and last stage 

 is into the mature coats of the male and female adult. Three 

 summers will be nearly the time required for these changes. 

 The " saddleback" has a wide distribution, influenced greatly 

 by the nature and distribution of the ice, and performs a 

 migration north in the spring, and south in the winter. 

 Dr Wallace gave numerous additional details regarding its 

 natural history, from personal observations in the Greenland 

 seas during the year 1860. 



2. Phoca leonina, 0. Fab. (The " Bladdernose " of the English sealers.) 



No sealers, as far as he was aware, had ever seen such a 

 seal as that described by Otho Fabricius in his " Fauna 

 Grsenlandica," viz., with a straight line of brown on its back, 

 as that author describes this seal in its second year. Crantz 

 and Fabricius disagree regarding the localities which it fre- 

 quents ; the one affirming that it is found mostly on great ice 

 islands, where it sleeps in an unguarded manner, while the 

 other states that it delights in the high seas, visiting the 

 land in April, May, and June. Both authors are correct, 

 though not in any exclusive sense. The "Bladdernose" is 

 found all over the Greenland seas from Iceland to Spitzbergen 

 and Nova Zembla. 



3. Plioca hispida, Mull. (Phoca fcetida, 0. Fab. Net silc of 

 Greenlanders.) 



The smallest seal in the Greenland sea. It is chiefly seen, 

 and taken as a curiosity, by the whalers, who call it the 

 11 Floe-rat," as it is always found on floes of ice, or quietly 

 swimming about in the floe waters. 



They appear to be confined to high latitudes, and espe- 

 cially to the parallels of 76° and 77° north latitude in the 

 Greenland and Spitzbergen seas, and it is in those latitudes 

 that the whalers find them. 



4. Dr Wallace described a fourth species of seal, which 

 forms a considerable source of the Greenland seal fishery, 



