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 × 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 feet long (1.80 × 1.30).
Range.—Pacific coast of N. A., Alaska to Lower California.