NATURAL SCIENCES OF PHILADELPHIA. 39 



Larus smithsonianus. 



Winter resident ; verj-^ abnndant ; the characteristic and onl}'- 

 common bii'd of the famil}' throughont that season. I have been 

 repeatcdl}^ assured that some of the " sea-gulls," as this species is 

 called in distinction from the smaller kinds, remain all summer, 

 but have never seen any at that season, and doubt the statement, 

 except perhaps in its application to diseased or otherwise disaliled 

 individuals. Some, however, certainly linger longer in spring than 

 would have been anticipated, being seen almost until June. There 

 is little falling off in their numbers in March; but most of them 

 pass northward early in April, about the time that the Terns and 

 Ghrcecocephali make their appearance. A few arrive in Septeml:ter, 

 but the}^ are not plentiful until the latter part of October. In 

 consequence of being rarely molested, the}' become quite familiar, 

 often mixing with the tame geese about the fort, and permitting 

 themselves to be approached within a few feet ; still, as a rule, 

 they show that they have an excellent idea of gunshot range. 

 Three styles of these gulls are easily distinguished. The birds of 

 the year are smokj'-brown (becoming grayer towards spring), and 

 differ in this respect from the young of any other species occur- 

 ring here. The birds hatched the previous summer but one are 

 pale gra3'ish, with the blue of the mantle showing in irregular 

 patches, the primaries wholly black, and the rectrices either the 

 same or white with a terminal black bar. The birds in their 

 third 3'^ear are in perfect plumage, but show the dusky streaking 

 of the head and hind neck characteristic of the winter plumage. 

 The bills of the birds of the first class are black; of the second, 

 flesh-color, black-tipped; of the third, j-ellow, with or without 

 the orange spot at the angle of the gonys. Most of the old birds 

 regain their nuptial dress before leaving. They are rather silent 

 during the winter, being rarely heard except when quarrelling for 

 food; but in April, before they move off, the air resounds with 

 their hoarse cries. Among the substances found in the stomach 

 were the remains of a marsh-hare, though I hardly think that the 

 animal could have been captured alive. 

 L. delawarensis. 



Spring and fall ; common, and jjrobabb/ also a winter resident, 

 although I did not identify it at that season.^ 



1 In winter the head and hind neck of this species are definitely njiotled 

 with blackish. In the case of the last species, and of, probably, the whole 

 1871.] 



