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NEW YORK STATE MUSEUM 



dilated to afford the necessary articular surface for the palatines. 

 These bones do not meet anteriorly in any of the Cathartidae, but 

 form the usual palatopterygoidal articular groove for the rostrum 

 of the sphenoid. 



From the examination of the skulls of immature specimens of 

 Cathartes a. septentrion a l i.s , I am inclined to be- 

 lieve that the orbito sphenoids will be found to exist in the crania of 

 the representatives of this family as separate ossifications. 



Carrying our investigations forward again, we meet with those 

 interesting ossifications the maxillo palatines, which still remain un- 

 described for the group now under consideration. In Cathar- 

 tes a. septentrionalis they are almost entirely hidden 

 from our sight upon a basal view of the skull ; and it is only 

 their mesial margins that can be observed upon this aspect [see 

 Hayden's 12th An. Rep't, pi. 22, fig. 120]. Upon lateral view, 

 however, they are plainly visible, and are seen, in each case, 

 to be a subvertical lamina of bone that reaches from the 

 mesial apex of the triangular and horizontal portion of the 

 ossification, upward and outward to fuse with the correspond- 

 ing nasal and rhinoseptal ossification above. "What I have 

 called the horizontal portion, is a thin lamellar piece of bone, 

 growing out from the maxillary toward the middle line to meet 

 the inferoanterior angle of the subvertical plate already described 

 in the last paragraph. This is the arrangement in general in all 

 of the Cathartidae, and can be easily comprehended by a study of 

 any of the numerous vulturine skulls that illustrate this treatise. 

 Huxley placed these Cathartidae among his Desmognathae, and of 

 the desmognathous skull he has said in part that " The maxillopala- 

 tines are united across the middle line, either directly or by the in- 

 termediation of ossifications in the nasal septum." [Zool. Soc. 

 Lond. Proc. 1867. p. 435, 436, 460, 463] With these birds this is 

 the case provided we consider the horizontal, internasal ossification 

 of the rhinal chamber, described above, as a portion of the nasal 

 septum ; for an examination of the skulls of the young of Cath- 

 artes a. septentrionalis plainly shows, that it is a separate, 

 ossification and not developed by the maxillopalatines themselves. 



My former monograph upon the Osteology of the Cathartidae 

 had in it some additional points upon the skulls of these birds not 

 as yet herein mentioned, and before proceeding to notice the man- 

 dible and other parts, we will allude to them. Among other things, 

 1 said that the posterior wall of the orbital cavity is quite smooth 



