STERNA FORSTERI : FORSTER S TERN. 



369 



FORSTER'S TERN. 

 Sterna forsteri Nutt. 



Chars. Like the last ; larger, tail longer, and wings shorter. Wing 

 of adult, 950-10.50; tail, 6.50-8.00, thus often beyond the ex- 

 treme oi Innindo, and nearly as in macruraj bill, 1.66 (i. 50-1. 75), 

 and about 0.40 deep at base (in hirundo rarely if ever so deep) ; 

 whole foot, about 2.00. Little or no plumbeous wash below ; 

 inner web of the outer tail-feather darker than the outer web of 

 the same. Young and winter birds may be distinguished from 

 hirundo at gunshot range ; the black cap is almost entirely 

 wanting, and in its place is a broad black band on each side of 

 the head through the eye ; several lateral tail-feathers are largely 

 dusky on their inner webs, their outer webs being white. 



Though one of the common and generally distributed 

 Terns of North America, For- 

 ster's is rare in New England, 

 where it is not known to breed. 

 It is commonly spoken of as only 

 a casual or irregular visitor ; but 

 probably no season of migration 

 passes without the presence of 

 the bird along our shores. It 

 is chiefly seen in the fall, during 

 the month of September and in 

 immature plumage. The first 

 definite record for Massachu- 

 setts, if not for New England, seems to have been 

 given by Mr. Brewster (Am. Nat., vi, 1872, p. 306). Mr. 

 Purdie notes it from the Massachusetts coast (Am. Nat., 

 vii, 1873, p. 693), and Mr. N. T. Lawrence speaks of two 

 Rhode Island specimens (For. and Str., x, 1878, p. 235). 

 It has lately been ascertained to breed on the Virginia 



Fig. 78. — Foot of Forster's 

 Tern. Nat. size. 



