Dec. 1887.J 



AND OOLOGIST. 



199 



my reason for so believing brings nie to what I 

 wish to say concerning the birds that invariably 

 lay two eggs in this section, which is this : 

 one day elapses between the days on irliich the first 

 and second eggs are laid — that is if the bird lay 

 its first egg on Monday, it will miss Tuesday 

 and lay the second on Wednesday. I first ob- 

 served this some years ago by watching nests 

 of the domestic Pigeon and have since devoted 

 much time to the class of birds which lay two 

 eggs. I have examined many nests of Rub}^- 

 throated Hummingbird, Whippoorwill, Night- 

 hawk, Turkey Buzzard, Black Vulture and 

 Mourning Dove, and all were found to conform 

 to the above rule. 1 have never seen this fact 

 mentioned b}' anj^ writei", nor have I met with 

 a collector who had noticed it, and Mr. Norris 

 writes me that he is confident it has never been 

 mentioned in any work on ornithology and 

 oology. To me it seems almost incredible that 

 so curious a thing should have been entirely 

 overlooked by all naturalists, and it was with 

 some hesitation that I decided to mention the 

 fact so far in advance of the coming season 

 when the proper investigations may be made ; 

 however, I have the satisfaction of knowing 

 that when the matter is tested my statements 

 will be verified. 



It is well that the oologist should be informed 

 of the elapsing of this intei'val as he may allow 

 sets to be completed which he would otherwise 

 take while incomplete. 



I earnestly desire the cooperation of collec- 

 tors everywhere, specially those who have op- 

 portunities to observe the Western Humming- 

 birds, Ground Dove, Chuck-will's Widow and 

 others whose normal number is two, and if they 

 conform to the same rule — and by analogy it 

 would seem they do — the natural deduction 

 will be that whei'e this uniform interval occurs 

 between the depositing of the first and second 

 eggs, two complete the set and when a third 

 egg appears it is laid by another bird. 



Although this should serve only as a means 

 of ascertaining what species lay but two eggs, 

 it may go just so far in determining the vexed 

 question of how many eggs constitute a set. 

 Therefore, it is hoped that collectors will give 

 this class of birds the attention they deserve, 

 and let their fellow' collectors have the benefit 

 of their observations. To the thoughtless one 

 who may otherwise think me in error, I will 

 say that the nest may be completed and one 

 egg laid when found and should he return on 

 the following day and find the set complete, 

 this only proves the first egg had been depos- 

 ited one day prior to the finding. 



Omissions From the List of the 

 Birds of Bristol County, Mass. 



BY A. C. BENT, TAUNTON, MASS. 



In Mr. F. W. Andros' list of birds of this 

 county in the O. and O. for September, 1887, I 

 noticed the omissions of several species which 

 occur tolerably regularly, and others which are 

 considered very rare or accidental. 



The most noted of these species is the Yellow- 

 bellied Sapsucker {Sphyraprns varius). This 

 bird, although by no means common, could 

 hardly be overlooked by collectors of any expe- 

 rience. 



As a summer resident it is very rare, although 

 I have had eggs brought to me said to be of 

 this species. It occurs in Bristol County as a 

 fall migrant in rather sparing numbers. I have 

 never seen it in the spring. It frequents the 

 same localities as the Hairy Woodpecker, being 

 more often seen in the woods than in open 

 places. The birds are shy and rather difiicult 

 to shoot on account of their knack of keeping 

 out of sight; they dodge around the trunks of 

 trees so skillfully that it requires considerable 

 patient waiting to shoot them. I have three 

 records of this bird for this fall. 



Another bird, not included in the list, came to 

 my notice several years ago, viz., the Blue- 

 gray Gnatcatcher {Polioptila ccerulea). 



This is an exceedingly i-are bird in this State, 

 and probably only an accident;il straggler from 

 the South. A farmer residing at Nippenicket 

 Pond brought me an egg^ unquestionably of 

 this species, which he found in a small nest re- 

 sembling a Flycatcher's, built in the fork of a 

 small fruit tree. His description of the nest and 

 bird, which I was unable to procure, coincided 

 with this species, and I know of no New 

 England egg with which it could be confused. 

 Of course, this is rather poor authority on 

 which to establish a record, still I mention it to 

 show that the species might occasionally be 

 found to breed here. Audubon says he " saw it 

 on the border line of Upper Canada, along the 

 shores of Lake Erie." On Dr. Brewer's author- 

 ity, it is found in Massachusetts and as far 

 north as the Canada line, and Dr. Coues states 

 its habitat as North to Southern New England. 



Only one species of Oidemia was mentioned. 

 0. per spkil lata, or Surf Scoter, commonlj^ known 

 by the gunners on the coast as the Skunk head 

 Coot. In addition to this species, we have the 

 Velvet Scoter or White-winged Coot (O./tisca), 

 which is more common than the preceding and 



