30 
COLYMBID.y, 
The eggs are two in number, according to the state¬ 
ment of undoubted authorities, and are said to resemble 
those of the Northern Diver in every respect, but that 
they are smaller in proportion to the size of the bird. 
We hope to include a representation of the egg in a 
future number, having at present no specimen on which 
we can sufficiently rely. 
The Black-throated Diver measures about twenty-two 
inches in length; the beak from the forehead two inches 
two lines; the wing from the carpus to the tip twelve 
inches; the tarsus two inches and a half; the outer toe 
three inches and three quarters. 
The plumage, See., of the adult bird are as follows : 
the upper part of the head, the nape and back of tlie 
neck are cinereous dusky; the chin is black as well as 
the throat and forepart of the neck; the base part of the 
front of the neck reflects purple ; the throat is ornamented 
by a white band, barred with black; the sides of the 
neck, from the ear-coverts to the base, are covered with 
black and white feathers in waving lines; the root of 
the neck is green, which colour divides the plumage of 
the back from the dusky colouring. The entire upper 
plumage of back, wings, and tail is black ; the tippet is 
ornamented with rows of white spots; the scapulars the 
same, having two oval white spots on each feather near 
the tip ; the shafts of these feathers are all black; the 
wing coverts are ornamented all over with smaller white 
spots, disposed in rows, caused by a white triangular 
mark on the tip of each feather; the quills are dusky. 
The sides of the upper part of the breast are marked 
by black and white streaks, which form waving lines; 
all the under parts are white ; the beak and legs are 
black, the webs pale dusky ; the eyes are red. 
