CLASSIFIED INDEX. i7l 



TUBINARES. 



Nostrils tubular ; horny covering of bill consisting of several dis- 

 tinct pieces, separated by more or less marked grooves; terminal 

 portion of bill produced into a strong hook ; feet fully webbed an- 

 teriorly; hallux rudimentary, consisting of an elevated sessile, often 

 minute, claw, sometimes wholly absent ; wings usually very long. 



PROGELLARIIDM (PETRELS). 



Nasal tubes near together, laid side by side upon the culinen, the 

 nostrils opening anteriorly; wings lengthened; hind toe present, 

 though sometimes minute. 



Procellaria pelagica, STORM PETREL, III. 17< 



PTGOPODES. 



Legs inserted far back, tarsi extremely compressed ; anterior toes 

 fully webbed, or strongly lobed, with broad flat nails ; bill extremely 

 variable. 



ALCIDM (AUKS). 



Bill variable; anterior toes fully webbed and armed with strong 

 claws, hallux entirely absent; lores feathered, tail always short; 

 nostrils without overhanging membrane. 



Alca torda, RAZOR-BILL, IV. 141 



Fratercula arctica, PUFFIN, II. 141 



Mergulus alle (M. melanoleucos, Alca alle), LITTLE AUE^ IV. 125 



Uria troile, GUILLEMOT, IV. 109 



PODICIPEDIDM (GREBES). 



Bill variable in shape, but always elongate; nostrils variable, 

 without overhanging lobe; wings very short and concave; tail 

 rudimentary, consisting of a tuft of downy loose webbed feathers 

 without perfectly-formed rectrices; toes lobate and semipalmate. 



Podiceps fluviatilis (P. minor), LITTLE GREBE, III. 29 



STEGANOPODES. 



Hallux united by web to inner toe ; bill longer than head, with 

 sharp cutting edges, and generally with a curved maxillary terminal 



