SYNOPSIS. XXXI. 



ORDER XV. PALMIPEDES. 



BILL various: tarsi short, often placed far back- 

 wards; toes generally four; the anterior ones 

 palmated, or semi-palmated ; occasionally all the 

 four toes united ; hind toe sometimes wanting. 



Gen. 78 STERNA. Bill as long as, or longer than the 

 head, nearly straight, compressed, tapering, slender, sharp- 

 pointed ; mandibles of equal length, upper one slightly 

 bending at the tip : nostrils near the middle of the bill, ob- 

 long, linear, pervious: tarsi short; tibia naked for a short 

 space above the heel; toes four, the three anterior ones 

 united by membranes deeply concave in front, or semi- 

 palmated; hind toe free: wings very long, acuminated; 

 first quill longest: tail generally forked. 

 S. Caspia, Pall. 



S. Cantiaca, GmeL v. 2, p. 177 



S. Dougallii, Mont. - v. 2, p. 179 



S. Hirundo, Linn. v. 2, p. 181 



S. Anglica, Mont. v. 2, p. 183 



S. stolida, Linn. 

 S. leucoptera, Tern in. 



S. nigra, Linn. v. 2, p. 184 



S. minuta, Linn. v. 2, p. 186 



Gen. 79. LARUS. Bill moderate, strong, compressed, 

 cultrated, bending downwards at the tip; lower mandible 

 with a prominent angle beneath: nostrils lateral, linear, 

 medial, longitudinal, pervious: tibia naked above the heel; 

 tarsi moderate; three toes before, entirely palmated; hind 

 toe free, short, articulated high on the tarsus: wings long; 

 second quill longest. 



L. glaucus, Brunn. - v. 2, p. 191-193 



L. Islandicus, Edmondston. 



L. argentatus, Brunn. - - v. 2, p. 194 



