forster's tern. 53 



usual limit, but we might with as much truth say that it is difficult 

 to account for birds so regularly keeping within certain limits. When 

 those of this class find themselves farther from home than they 

 intended, it does not cost them much labor to correct the mistake. 



This is the only record I have of the species in Ontario, and the 

 visit can only be considered accidental, as the summer home of the 

 species is far to the south. 



They breed in colonies on the coast of Central America and on 

 the larger West India Islands. 



Subgenus STERNA. 

 STERNA FORSTERI Nutt. 



25. Forster's Tern. (69) 



Like the Common Tern ; larger, tail longer than wings. Wing of adult, 

 ■94-104; tail, 64-8, thus often beyond the extreme of hirundo, and nearly as in 

 paradisma ; bill, Ig (l^-ljji-^'"'! about 2-5 deep at base (in hinmdo rarely if 

 ■ever so deep); tarsus seldom down to J; whole foot, about 2. Little or no 

 plumbeous wash below ; hwer web of the outer tail feathers darker than 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 the inner web ; their outer webs are white. 



Hab. — North America generally, breeding from Manitoba southward, in the 

 United States to Virginia, Illinois, Texas and California ; in winter, southward 

 to Brazil. 



Eggs, two or three, from greenish- white to drab, blotched and spotted with 

 brown and lilac of different shades. 



This is another of the sea swallows, a name which is indiscrim- 

 inately applied to all the terns. The species is abundant and widely 

 distributed. It is one of those found by Dr. Macallum breeding on 

 Mohawk Island, in Lake Erie. Mr. Saunders reports it breeding on 

 the St. Clair Flats, and Macoun speaks of it breeding abundantly 

 in Lake Manitoba, Waterhen River and Lake Winnipegosis. Farther 

 south, it is known to breed in Virginia, Texas, Illinois and California. 



Throughout Ontario generally, it is only a migrant in spring and 

 fall. It is usually in company with the Common Tern, which it closely 

 resembles, the points of diiference being readily observed when the 

 birds are placed side by side. 



