54 



ALLIED TERN. 



Order XV.— PALMIPEDES. (Temmhwh.) 



Family LARIDM. (Bonaparte.) 



Genus Sterna, f Linncens.) 



Generic Characters . — Bill as long or longer than the head, nearly straight, 

 compressed, tapering, edges sharp, pointed, mandibles of equal length, the 

 upper one slightly curved towards the point; nostrils near the middle of the 

 beak, slit longitudinally, and pierced from side to side. Legs small, naked 

 above the knee for a short distance; tarsi very short; four toes, the three 

 anterior united by membranes, deeply concave in front; hind toe free; 

 middle claw longer and sharper than the others. Wings very long, pointed, 

 the first quill feather the longest. 



ALLIED TEEN. 



Sterna affinis. 



Sterna affinis, 



' ' media, 



" Arahica, 

 Thalasseus affinis, 

 Hirondelle de mer voyageuse, 

 Riippeir s Seeschivalbe, 



TeMMINCK. RtJPPELL. 



Horsfield; Lin. Trans., vol. xiii, p. igg. 



Ehrenberg. 



Bonaparte. 



Of the French. 



Of the Germans. 



Specific Cha7'acters. — Middle toe with claw longer than the tarsus; beak 

 long, yellow; feet black; wings pass the end of the forked tail by an inch 

 and a half or more. Length fifteen inches; carpus to tip eleven inches; 

 beak two inches and nine tenths; height at base seven lines; tarsus eleven 

 lines; middle toe and claw one inch and one fifth. 



The Allied Tern, so called by reason of its affinities with the Sandwich 

 Tern, was introduced into the European list by Temminck, and has 

 been admitted as an European species by Bonaparte, Schlegel, and 

 Deu'land. 



