CATALOGUE OF VERTEBRATES. 629 



S. sandvicensis, var. acuflavidus, Cabot. Cabot's Tern. 



Bill deep black, with whitish tip ; otherwise much like pre- 

 ceding. Length, 15 inches; wings, 12| inches; tail, 6 inches, 

 forked for 2| inches ; bill, 2 J inches. A southern form ranging 

 north on the Atlantic coast to Southern New England. Rare. 

 Same as Thalasseus cantiacus, Sandwich Tern. 



S. trudeaui, Aud. Trudeau's Tern. 



Mantle bluish gray ; no black on head, but a dusky stripe on 

 each side ; general color white and pearl gray ; lower parts pure 

 white in winter ; bill yellowish, with black middle in summer, 

 with yellow tip, only, in winter. Length, 15 J inches; wings, 

 10 inches; tail, 5 inches or more, forked for about one-third of 

 its length. Inhabits "Atlantic coast of South America ; casual 

 on Atlantic coast of United States (New Jersey)." — Ridgway. 



" Met with rarely, in winter only, being a northern species." 

 — [C. C A.] Probably refers to the arctic tern. 



S. forsteri, Nutt. Forster's Tern. 



Inner web of outer tail feather dusky towards end, outer web 

 all white ; in summer, above pearl gray ; white below ; top of 

 head black ; bill orange, with dusky tip ; feet reddish orange ; 

 in winter, top of head white ; sides of head striped ; tail less 

 forked; bill with more dusky; feet paler. Length, 14| inches; 

 wings, 10 inches; tail, 5 to 8 inches, forked for 2| to 5 inches. 



" Occasionally met with during the winter, but rarely." 



S. hirundo, L. {tvilsoni, Lawr.) Wilson's Tern. Common Tern. Sea 

 Swallow. 



Inner web of outer tail feather all white; outer one dusky; 

 summer plumage, lower parts grayish white ; upper parts pearl 

 gray ; top of head black ; tail mostly white ; bill red, blacken- 

 ing towards tip ; feet rich orange vermilion ; in mnter, white 

 encroaches on black of head from the front ; lower parts pure 

 white; bill and feet duller. Length, 13 to 16 inches; wings, 

 10 inches ; tail, 5 to 7 inches, forked about half way. 



"Appears oif the coast April 15th. Called 'sheeps-head gull.' 

 Breeds along ' the shore,' depositing its eggs on the drift-grass. 

 Is found along the rivers Delaware, Raritan and Hackensack." 



S. paradissea, Briinn. {macrura, Naum.) Arctic Tern. 



Bill carmine throughout ; tail and tips of secondaries white, 

 in sharp contrast with grayish cast of rest of plumage. Length, 



