418 Annals of the Carnegie Museum. 



9. Hyoid apparatus with large, united ceratohyals, and a peculiar 

 bony outgrowth on either side of the first basibranchial, extending 

 forwards. 



10. Manubrium of sternum erect, large, and continuous with the deep 

 carina. The xiphoidal extremity of this bone has an elliptical fenes- 

 tra on either side. Costal processes low, and usually six h?emapo- 

 physial facets on each costal border. Coracoidal grooves unite in 

 front. 



11. Furculum of shoulder girdle firmly united below. 



12. The humerus only is pneumatic in the pectoral limb. 



13. A well-developed patella present. Fibula short, extending only 

 so far as the lower end of fibular ridge of tibio-tarsus. 



14. The tendinal bridge at antero-distal end of tibio-tarsus at right 

 angles to long axis of shaft. The inner condyle the larger and more 

 elevated. 



15. General skeletal characters of pes agree with other Psittaci. 



Nci^ative Characters. 



1. Vomer absent. 



2. Basipterygoid processes not developed. 



3. No hypocleidium on os furculum, and this bone does not meet 

 the scapular process of coracoid. 



4. Propubis of pelvis absent. 



5. Pelvic liml) non-pneumatic. 



T/ie fo/Io-io/'/i!^ osfcfl/og/cal characters when associated in the sajiie 

 skeleton characterize a representative of the family Psittacid.e of the 

 siil^order PsniACi . 



1. Superior osseous mandible of skull with cultrate dentary margins, 

 usually I -notched on either side ; arched as in Raptores. (The notch- 

 ing is absent in Ara.) 



2. External orbital periphery usually completed in bone. 



3. A movable cranio-facial hinge present in the skull. 



4. A single mandibular facet on either quadrate. 



5. The maxillo-palatines a spongy mass, fusing with the surrounding 

 bones. 



6. The rami of the mandible unusually deep, the symphysis trun- 

 cated anteriorly. 



7. Xiphoidal border of sternum rounded, unnotched ; and may be 

 pierced hy a foramen on either side. 



