THE OOLOGIST. 



45 



Memoranda of Eggs Collected in 

 1877. — The following is a brief abstract of 

 dates on wliich eggs were collected this 

 year in Oneida County, N. Y., at Bangor, 

 Me., and at Chicago, Ills. : 

 Oneida County, iV. Y. 



Red-shouldered Hawk, 

 Common Crow, 

 Robin, 



Broad- winged Hawk, 

 Red-tailed Hawk, 

 Great Northern Shrike, 

 Meadow Lark, 

 Purple Finch, 

 Belted Kingfisher, 

 Crow Blackbird, 

 Sparrow Hawk, 

 Spotted Sandpiper, 

 Bobolink, 

 House Wren, 

 Red-winged Blackbird, 

 Wood Thrush, 

 Black-billed Cuckoo, 

 Yellow-winged Sparrow, 

 Common Rail, 

 Blk'-th't. Green Warb., 

 Bangor, Me. 



April 28 

 28 

 28 

 28 

 30 



May 5 

 16 

 17 

 17 

 18 

 24 

 25 

 28 

 30 



June 2 



..2 



9 



15 



July 10 

 27 



4 4* 



Ruffed Grouse, 

 Red-tailed Hawk, 

 Robin, 



Red-shouldered Hawk, 

 Common Crow, 

 Cooper's Hawk, 

 Great Northern Shrike, 

 Killdeer Plover, 

 Wilson's Thrush, 

 Yellow-billed Cuckoo, 

 Chicago, Ills. 



April 16 

 25 

 27 

 28 

 30 

 1 

 5 

 28 

 1 

 5 



May 



June 



Hairy Woodpecker, 



April 30 



2 eggs. 



Robin, 



30 



44 



Black-capped Titmouse, 



May 9 



6 



Least Flycatcher, 



10 



2 



Orchard Oriole, 



23 



4 



Baltimore Oriole, 



23 



5 



Black-throated Bunting, 



25 



4 



Bittern, 



June 1 



4 



Spotted Sandpiper, 



11 



3 



Cow Birds' Eggs. — Collectors interest- 

 ed in the history of the Cow Bird, frequent- 

 ly find themselves in search of a cause to 

 account for the hatching of the Qgg of this 

 bird, sooner than those with which it is de- 

 posited. The mystery is rather heightened, 

 when it is considered that the egg is in gen- 

 eral larger and thicker-shelled than its nest- 

 mates. Perhaps the theory advanced by 

 Mr. Gentry may add light to the subject. 

 He states : "Experience has taught us that 

 a setting of eggs is sometimes longer in 

 hatching than others. The difference of 

 time is evidently due to variation in the 

 amount of heat to which the eggs are sub- 

 jected. New the egg of the Cowbird being 

 perceptibly larger than the others, would 

 receive more heat from the body of the fos- 

 ter-mother than the latter's own, for the 

 obvious reason that it would be in closer 

 proximity to the source of heat. This in 

 our judgment will satisfactorily explain its 

 much shorter period of incubation. Were 

 the eggs hatched by their rightful mother, 

 it is probable that the period Avould vary 

 but a trifle, if any, from that of the Rusty 

 Blackbird." 



A CURIOSITY in the shape of a green hen's 

 egg was recently ' ' collected" in New Hart- 

 ford, N. Y. It was of the usual size and 

 form, but was minus the usual proportion 

 of yolk. 



*Number of sets taken on the same day. 



Illustrated Oology. — We have been 

 informed that the publishers of Dr. Jasper's 

 Birds of North America, propose to issue 

 under the direction of Dr. Brewer, of Bos- 

 ton, a series of parts on North American 

 oology, to be illustrated by colored plates 

 of all the eggs known to the present time, 

 embracing upwards of seven-hundred spe- 

 cies and varieties. This is a great enter- 

 prise, and it is sincerely hoped the project 

 will meet with success. The parts, to the 

 number of about ten when the work is com- 

 plete, are to be sold by subscription at one 

 dollar each. 



