CATALOGUE OF VERTEBRATES. 627 



"Off the coast from November 15th or thereabouts until 

 March. Probably does not ascend the rivers any distance. 

 Appears to prefer the open sea to the bays. Go north to breed 

 in March. Are not as abundant at any time as the following 

 species." 



Li. delawarensis, Ord. Ring-billed Gull. 



Plumage like preceding; feet olivaceous; webs yellow; bill 

 yellowish, with black band at tip. Length, 20 inches ; wings, 

 15 inches. 



" Makes its first appearance about October 1st, and is abundant 

 on our sea-board and along our rivers until April, when they 

 have all left for their breeding-grounds. This gull is very 

 abundant on the Delaware, as far up as Philadelphia, but 

 seldom ascends farther." 



L. atricilla, L. (Chrcecocephalus, Eyt.) Black-headed, or Laughing Gull. 



Bill and feet dusky carmine ; tarsus longer than middle toe ; 

 lower parts white, roseate in breeding season ; head sooty slate, 

 white in winter ; mantle leaden ; five outer primaries black, rest 

 of quills gray ; young brownish and white. Length, 15 to 17 

 inches; wings, 13 inches; tail, 5 inches. 



" Abundant, not only on the coast but in Delaware Bay. 

 Seldom ascends farther up the river than Philadelphia. Breeds 

 in Cape May county. Is first seen about April 1st, and gen- 

 erally have all disappeared by the middle of October." 



L. Philadelphia, Ord. Bonaparte's Gull. 



Tarsus not longer than middle toe (1 J inches) ; bill deep 

 black ; plumage generally white ; head dark gray in summer, 

 white in winter; mantle pearl gray; quills white and pearl 

 gray, tipped with black ; feet orange red, paler in winter. 

 Length, 13 inches; wings, 10 inches. 



" This gull is abundant on our coast and along our rivers 

 from April 1st, but does not make a prolonged stay, and never 

 breeds within State limits. This species ascends the Delaware 

 as far as Trenton more frequently than any other species. Are 

 not seen during the winter." 



