ON THE COLYMBUS IMMER. 235 



fail ; and four feet five inches between the tips of 

 the wings. Its weight was seven pounds and a 

 half. The bill is straight, pointed, very strong, 

 and measures four inches from the side of the 

 mouth to the extremity. The upper mandible 

 projects a little beyond the under one, and is black 

 on its superior ridge. The under mandible is of 

 a light blue colour. The nostrils are pJaced near 

 the base of the upper mandible, and are divided 

 near the middle by a cartilaginous kind of bar, 

 which arises from the upper, and goes across, but 

 is not inserted into the under mandible. The 

 irides are of a beautiful bay-brown, bounded by 

 a light blue line almost as broad. Back from the 

 latter, or the sclerotic, is another brown circle, 

 nearly of the dimensions of the iris, but less deep 

 in the colour. The external border of the eyes 

 is white. The upper part of the head and sides 

 of the face, are black and grey mixed. The chin 

 is white. The upper part of the throat grey and 

 white. The neck is of a dusky grey and white. 

 The breast and belly are white, and have a glossy 

 appearance. A blackish bar crosses the vent. The 

 tail is very short. The shoulders and scapulars- 

 are of a mixture of black and ash colour, and 

 most of the feathers are tipped with white. The 

 inner coverts are white. The feathers on the back 

 and rump are short, and of a dusky-ash colour^, 

 inclining to brown. The feet and legs are large 



