RHINOCEROS AUKLET. 
15. Cerorhinca monocerata. 11 inches. 
These birds have a much smaller bill than the Puffins; in 
the summer plumage there is a small horn at the base of the 
bill from which it is given its name. These birds do not 
stand upright as do the Puffins; but sit upon their tarsus. 
Nest. —A single egg is laid in either burrows or in crevices 
of the rocks, usually without any attempt at nest making 
(2.70 x 1.80). 
Range.—Coast and islands of the northern Pacific. Breeds 
from Oregon to northern Alaska. 
CASSIN AUKLET. 
16. Ptychoramphus aleuticus. 9 inches. 
A plain appearing bird, breast and throat grayish and belly 
white with blackish upper-parts relieved only by a small white 
spot over the eye. This Auklet is fairly abundant on the 
Farallones and islands off the Lower California coast. 
Nest. —A single egg, dull white, the inside of the shell being 
a pale green when held to the light. These are laid in burrows 
or tunnels under the rocks, at times three or four f'eet long 
(1.80 x 1.30). 
Range.—Pacific coast of N. A., Alaska to Lower California. 
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