256 



OSTEOLOGY OF TUBINARES AND STEGANOPODES. 



tion that their median tree margins seem to anchylos with the corre- 

 sponding edges of the palatines over which they lay; consequently upon 

 this view they are shut out of sighl and do not appear in the interpal- 

 atine space. 



The vomer is very Long, being half a hollow cylinder behind, with its 

 convex surface downward; the posterior end of this joins the palatines 

 in the usual way. Below, it is longitudinally grooved in the median 

 line. This groove is continued forward as a car i nation on the anterior 

 portion, to terminate in a little spike in front. The concavity of the 

 half cylinder and the anterior portion form together a loug gutter for 

 the rostrum of the sphenoid. 



I'n.. 1. Complete skeleton of Oceanodroma fiircata. (Specimen 1G990, Smithsonian collection.) Life 



size. By the author. 



The pterygoid* arc slender, straight bones; their anterior heads meet 

 each other and the heads of the palatines, the lour forming a groove 

 above for the under convex surface of the presphenoidal rostrum. 



There is no sign whatever of the presence of basi pterygoid processes. 

 Huxley mentions their occurrence in Procellaria gigantea in his Classi- 

 fication of Birds. 



