1876.] Zoblogy. 239 
gregarious throughout the region over which we passed in 1873, Yel- 
lowstone River, etc., and I can say the same of Nevada, in the valley of 
the Payhee and Humboldt rivers. Frequently, while working our way 
slowly up the Grand Cafion of the Colorado River, where the plateau 
was over six thousand feet above us, with walls at an angle (from 
base to summit) of nearly eighty degrees, we found numbers of crows 
and ravens flying over our heads, or perched upon the projecting ledges 
of sandstone or basalt. Rather dismal to hear the croaking in such a 
locality, — the bottom of a gorge, one and a quarter miles below the sur- 
face. — W. J. Horrman, M. D. 
REMARKABLE Structure or Youne Fisues.— Dr. Günther, of 
London, has recently discovered that the young of the sword-fishes and 
Chetodus possess structures exceedingly different from that of the adult. 
In the young Chetodus the front of the body is shielded with large bony 
plates, which in one species are produced into three long, equidistant 
horns, which diverge ray-like from the body. In the sword-fishes the 
scapular arch is prolonged into a horn at the lower part, and the belly 
fins are wanting. There is no sword, but the jaws are long, of equal 
length, and both are furnished with teeth. As the fish grows, the scap- 
ular horn disappears, the ventral fins grow, and the uppér jaw is de- 
Veloped in excess of the lower. The long teeth disappear, and the 
upper jaw grows into the toothless, sword-like weapon which gives the 
fish its peculiar character. 
Uxusuan Nesting Sires or tae Nient Hawk AND TOWHEE 
Bunting. — A letter from Mr. William Couper, of Montreal, speaks of 
his having found the eggs of Chordeiles popetue on the flat roofs of build- 
ings in that city, and the nest of Pipilo erythrophthalmus in a small tree 
about three feet from the ground. In each of these cases the departure 
from the usual habit of the species is decided. — ELLIOTT Cougs. 
GGs or Boa-Constrictor. — My friend, Dr. Kunzé, has shown 
me an infertile egg of a boa which he lately obtained at the Central Park 
menagerie. The boa laid twenty-one eggs, each about the size of a 
hen's egg. The animal made the deposit in sight of her keeper and 
others. She laid two fertile eggs, and then a sterile one, in regular 
Succession ; each third egg was sterile. The fertile eggs had each a 
young boa within. One came out of its shell immediately after being 
laid, but soon died. All the others died within their shells. The sterile 
©8388 were albuminous throughout, and cut like cheese and smelled like 
< Perm oil. Could this be the balance of an impregnation received the 
year before? — S. Lock woop. 
SMALL Birps CAUGHT BY THE BurpocK.— At Lake George, a gen- 
tleman presented me with a skeleton of a humming-bird, firmly fastened 
to some burs, which he found on a burdock; and at the same time he 
found a live one on a plant near by. I was walking along one of our 
country roads, when I saw a yellow-bird (Chrysomitris tristis) fluttering 
