568 PUFFINID^ 



and under parts, are pure white, the other in which they 

 are shaded grey. In Iceland, and on the western side of 

 Davis Strait and Baffin Bay, the latter is chiefly to be found, 

 while at Ovifak in Greenland, the former abounds. Both 

 forms occur round Spitzbergen, but the grey-plurnaged birds 

 are in the majority. F. rodgersi, with only a light phase, 

 and with the back and rump interspersed with white, 

 inhabits Behring Sea, and F. glupischa, with pale-coloured 

 nasal-tubes, the North Pacific. The latter has a light and 

 a dark phase of plumage (Saunders). 



