22 NOTES ON THE 



the same date in the following month, or even a little lal er, 

 when they are found to have disappeared entirely. 



SPECIFIC CHARACTERS. 



Forehead, crown, sides of head, and occiput black, glossed 

 with green, which color extends below the eyes and under 

 which is a narrow white line; back and wings light bluish-ash; 

 the six outer primaries dark slate-gray on their inner webs; 

 quill shafts white; tail and its upper coverts grayish- white; 

 neck and entire under plumage pure white; bill and inside of 

 mouth bright vermilion; legs and feet black; bill very stout; 

 tail not deeply forked. In the young the back, wing coverts 

 and tail are mottled and barred with blackish-brown. 



Length, 22; wing, 17; tail, 6; bill, 3. 



Habitat, North America generally. 



STERNA FORSTERI Nuttall. (69.) 



FORSTER'S TERN. 



I was much gratified, after long waiting and fruitless en- 

 deavor to find whether this species of Tern ever reared its 

 young within our State, to have a clutch of the eggs sent to 

 me from Douglas county. Poaching collectors had many 

 times claimed to have obtained them, but their finds, with a 

 few generous exceptions, have contributed very little to local 

 natural history or a sense of personal obligations. Their ex- 

 ceedingly brief appearance, beginning about the 25th of April 

 and lasting but a few days, comparatively, led me to appre- 

 hend that the instinct of incubation was indicating the proximity 

 of their summer habitat, which ever kept me in expectation that 

 it would ultimately be found near at hand. The nest was 

 reported to have been located on a muskrat house entirely 

 surrounded by water, and consisted of a moderate quantity of 

 reeds and coarse grasses, very slightly hollowed, and con- 

 tained three eggs, which were not pointed at the smaller end 

 like some others of the same family but were decidedly ovate, 

 light brown with a wash of palest green, blotched and spotted 

 with dark brown, was more marked at the larger end. The 

 average measure of the three was; 1.75 by 1.12. It was obtained 

 June 7th, and the eggs were apparently fresh. 



SPECIFIC characters. 



Upper part, sides of head to a line just below the eye, and 

 hind neck, black; back and wings bluish-gray; primaries gray- 

 ish-white on the outer webs and dusky-gray on the inner next 

 the shaft, and over the entire web at the end; darker on inner 



