264 



BULLETIN OF THE 



separating the Yarmouth bird from those found in the Hudson Bay ter- 

 ritory." * 



In the following table of measurement-! of twenty-seven specimens, all 

 taken within ten miles of Cambridge, and all but two in December and 

 January, the extremes of size are as follows : Length, 4.70 and 5.75, both 

 specimens being females ; alar extent, 7.50 and 8.60, both specimens being 

 also females; wing, 2.33 and 2.63, also both females; tail, 2.15 (female) 

 and 2.G7 (male) ; tarsus, .G2 (male) and 7 7 (female). The average size 

 of these specimens is as follows: Length, 5.38 ; alar extent, 8.3 7 ; wing, 

 2.4 7; tail, 2 50; tarsus, .70. The females average a little smaller than 

 the males, but the difference is only slight. 



The largest specimen of the group of black-capped and black-throated 

 titmice cited by Professor Bairdf measures as follows: Length, 5.75; 

 alar extent, 8.37; wing, 2.75; tail, 2.86 (Parus septentrionalis, from the 

 Black Hills, Neb., Sm. Inst. No. 8827). A specimen of the P. carolinensis, 

 cited by the same author, measures as follows : Length, 4.62 ; alar extent, 

 7.00 ; wing, 2.50 ; tarsus, .60 (Sm. Inst. No. 706, from Washington, D. C). 

 So far as the length of the wing and tail are concerned, specimens are fre- 



Measurements of Massachusetts Specimens of Parus atricapillus. 



* Proc. Bost. Soc. Nat. Hist.. Vol. IX, p. 368, April, 1865. 

 t Birds of North America, p. 39u. 



