OCEANITIDai 457 



>6*. Bill shorter, its length from the tip 

 to the base raeasured straight, about 

 equal to its distance from the eye ; 



its colour black (Estrelata,-p. ill. 



6*. Sides of the palate with a series of 

 lamella; more or less developed, 

 rt'. Birds of large size ; wing about 20'0 ; 

 sixteen tail-feathers ; nasal tube long 



about half the length of the bill Oaaifraga, p. 482. 



h^. Birds of intermediate size ; wing about 

 lO'O ; fourteen tail-feathers ; nasal tube 

 shorter, about one third of the length 



of the bill Dajition, p. 485. 



c^. Birds of small size ; wing about 8'0 ; 

 twelve tail-feathers ; nasal tube very 

 short about one-fourth of the length 

 of the bill Prion, p. 487. 



B. Nostrils opening upwards, side by side on the 



top of the bill; no hind toe Pelicanoides, p. 493. 



C. Nostrils each enclosed in a separate long sheath 



and opening on either side of the bill between 

 the culminicorn and the latericorn. 



a. Tail short and rounded ; no trace of a hind toe ; 



lower mandible without longitudinal sulcus. 



a\ Base of the culminicorn wide, meeting the 



latericorn behind the nostrils Diomedea, p. 494. 



V. Base of the culminicorn narrowed pos- 

 teriorly, separated from the latericorn 

 behind the nostrils by membrane Tlialassogeron,-p. 501. 



b. Tail long and wedge-shaped ; hind toe repre- 



sented by a rudimentary claw ; a longitudinal 



groove along the lower mandible Phtebetfia, p. 505. 



Family I. OCEANITID^. 



Secondaries never more than ten in number; leg bones longer 

 than the v?ing-bones ; tarsi very long covered in front by a single 

 shield or by transverse scutes ; claws more or less flattened ; no 

 cseca; no basipterygoid processes; semitendinosus with an acces- 

 sory head ; ambiens, when present, not passing over the knee. 



