132 MANUAL 



ened body, are all characteristics of the Terns. They secure 

 their food — usually fish — by darting upon it, from high in 

 air, with the velocity and the true aim of an arrow from the 

 bow of an expert archer. Most Terns have a forked tail, so 

 that one can generally tell them, even while yet in the air, 

 from Gulls. They often occur a short distance inland, but 

 seldom stray far from the seacoast or its immediate vicinity. 

 Terns are social birds and fond of each others company ; throw 

 a dead tern even up high into the air and, if there be any liv- 

 ing terns near, even if not in sight at the time, numbers will 

 swoop down upon you in a moment. In general : Bill usu- 

 ally hard, horny, even at the point, and sharp tipped ; the 

 nostrils are always prominent and opening from one side of 

 the mandible to the other and are oblong slits — more or less 

 basal. Toes usually long compared to the short and weak tar- 

 sus ; webs not quite full, and concave rather than straight 

 edged. Even the young student, after a moment's examina- 

 tion, will hardly mistake the Terns for the Gulls. 



Genera, Sterna, The True Terns (14 species). 



Hydrochelidon, The Black Tern and ally. 

 Anous, The Noddy Tern. 



Sub-genera, Gelochelidon for The Gull-billed Tern ; Thalasseus for the 

 Caspian, Cayenne, Elegant, and Sandwich Terns ; Sterna [proper] for the 

 Wilson's, Forster's, Arctic, Roseate, Trudeau's, Least, Aleutian, Sooty and 

 Bridled Terns. The Sooty Tern is sometimes named Haliplana. 



The synonyms are hardly worth mentioning, being almost invariably 

 Sterna, (Sternula [little Sterna'] for The Least Tern,) and Thallasseus. 



Sub-family d RHYNCHOPINiE Skimmers 



The bill of this bird alone distinguishes it from anything 

 else in the bird kingdom. It is like a long, blunt pair of 

 shears, with part of the top (the upper mandible) broken off 

 part way from the tip which is then filed to a rounded point 

 as it lays upon its fellow. Otherwise it is a true Tern. Only 

 three species are, I believe, known to science ; one alone in- 

 habiting North America. 



Gents, Rhynchops, The Black Skimmer. 



