birds. m 



of the mandible : tongue nearly as long as the bill : 

 toes 3, all placed forwards. 



49. Uria. Bill strong-, slender, pointed; the upper man- 

 dible slightly bending towards the point, covered 

 with short feathers at the base : nostrils linear, in a 

 hollow at the base of the bill : tongue nearly as long 

 as the bill : toes 3, all placed forwards. 



50. Colymbus. Bill strong, straight, pointed; upper- 

 mandible longer, the edges of each turning inwards : 

 nostrils linear : tongue long, pointed, toothed each 

 side near the base : legs thin, flat : toes 4, the outer* 

 one longer; back-toe small, connected by a small 

 membrane to the inner-one: tail short, of 20 or more 

 feathers. 



51. Sterna. Bill straight, slender, pointed, a little 

 compressed: nostrils linear : tongue slender, pointed : 

 wings very long: toes 4, slender; the back-toe very 

 small, and unconnected with the rest: tail mostly 

 forked. 



52. Larus. Bill strong, straight, bending down at the 

 point, with an angular prominence on the under part 

 of the lower mandible : nostrils linear, broader on t\\Q 

 forepart, placed in the middle of the bill: tongue 

 slightly cloven: legs naked above the knees; toes 4; 

 the back-toe small, unconnected. 



53. Procellaria. Bill a little compressed, hooked at 

 the point : nostrils cylindrical, contained in a tube : 

 legs naked a little above the knees: toes 3 , placed 

 forwards, with a spur pointing downwards instead of 

 the back-toe. 



54. Mergus. Bill slender, a little depressed, with a 

 crooked nail at the point; the edges of the mandibles 

 with sharp serratures: nostrils small, somewhat ovafe, 

 in the middle of the bill : toes 3 forward, the outer- 

 one longer, and one behind, furnished with a web. 



55. Anas. Bill broad, depressed, obtuse, with a nail at 

 the point; the mandible edged with lamellate obtuse 

 serratures : nostrils ovate : tongue broad, obtuse, 

 fringed on the edges near the base : toes 3 forwards, 

 the middle-one longer, and one behind unconnected. 



56. Pelecanus. Bill long, straight, with a hooked nail 

 at the point.: nostrils concealed in a furrow : face and 

 gullet bare of feathers : toes 4, ail webbed together. 



