NEW YORK STATE MUSEUM 



Cathartes a. septentrio n a 1 i,s , completely coossifies 

 with the lower external half of the pars plana, but does not quite 

 come in contact with the maxillary bar. 



Essentially, Cat h arista urubu agrees with this, but this 

 portion in Sarcorhamphus g r y p h u s and Gymnogyps 

 cal i f ornianus often knitting as usual with the ethmoidal wing, 

 is produced downward, backward and outward, as a clublike process 

 to almost reach the zygoma. 



In such a form as Neophron percnopterus the ar- 

 rangement leans more toward the Falconidae than toward the 

 Cathartidae, though there is a positive step vultureward. In this 

 bird the superciliary portion has shrunk in size, articulates prin- 

 cipally with the margin of the nasal, while the body of the bone, 

 below, engages the entire border of the pars plana, and all the 

 sutural traces are usually permanent throughout the life of the in- 

 dividual [pi. 6, fig. 10]. 



As we pass falconward, the next interesting step is seen in the 

 lacrymal as it occurs in Gypogeranus serpen tarius, 

 where the superciliary part forms much the larger share of the 

 entire bone, while the body becomes a mere inbent osseous bar that 

 touches the pars plana at the angle. Here the inner margin of the 

 upper or superciliary portion meets the nasal and frontal bones for 

 its entire length ; the articulation being very close, but the suture 

 plainly visible. 



When we come to the Falconidae, a great number of interesting 

 forms of the lacrymal will be met with, and it will be seen to 

 present characters of excellent classificatory importance. Among 

 the vultures the lacrymal is pneumatic. This is likewise the case 

 with the large, quadrate pars plana, which in Cathartes shows a con- 

 siderable excavation upon its anterior aspect. Above this inter- 

 orbitorhinal partition a large vacuity exists [see pi. 6, fig. 9]. 



As for the mcscthmoid it meets the vault of the rhinal space 

 above in a spreading abutment ; from this point it takes a direction 

 downward and backward in the mesial plane, to become con- 

 solidated with the extremity of the basipresphenoid, below. Be- 

 hind, by the extension of its median osseous plate, it assists to com- 

 plete the orbital septum. This latter is quite entire in adult speci- 

 mens of Cathartes a. s e p t e 11 t r i o n a 1 i s and C a t h a - 

 r i s t a urubu, while in Gyparchus, the condors and others a 

 vacuity is always seen to exist near its middle | sec ITayden's 12th 

 An. Rep't, pi. 21, fig. 116J. 



