SmiKi.nr : Osteology of i hk Psittaci. 415 



shafts, and consequently but little dissociated from the ligaments that 

 descend from the corat oidal summits to meet for attachment on the top 

 of the ^>teinal manubrium. It is in form of the U-shaped ])attern, and 

 without a hypocleidium at the clavicular junction below. 



As already intimated above, and so far as the light I have on the 

 subject will at present permit me to judge, I believe that the shoulder- 

 girdle of Coniirns more nearly resembles these parts in some of the 

 owls than it does the corresponding lines in any other class of birds 

 with which I am accpiainted. 



0/ the Appendicular Skeleton. — The pectoral limb of this parrot 

 presents no very striking deviations from the average skeleton of the 

 wing as found in existing birds. 



The bones are all harmoniously balanced both as regards their rela- 

 tive lengths and calibres. 



Pneumaticity is enjoyed by the lunitcnis alone, as in Cacatna, and 

 this bone is here characterized by a short, though not inconspicuous, 

 radial crest, an ulnar crest devoted, as usual, to forming a canopy over 

 the ])neumatic fossa, in which are found the air-holes leading to the 

 interior of the humeral shaft. This latter is but little curved in any 

 direction, being subcylindrical and smooth. At the distal extremity 

 of the bone we find the trochle?e for articulation with the antibrachial 

 elements prominently produced, while on the obverse aspect a broad 

 and a narrow gutter is seen, which guide the passing tendons in 

 life. 



The radius is nearly straight for its entire length, differing from the 

 ulna in this particular, it having a considerable curve along its shat"t, 

 the concavity of which is on the radial side, and gives rise to quite a 

 wide interosseous sjjace. 



The carpal elements are two in number as usual, and they have the 

 form most commonly presented by these bones throughout the majority 

 of the Class. 



In the manus we find a carpo-metacarpus of the ordinary form for 

 birds generally. Its rather large pollex jjhalanx is without a claw, this 

 feature being likewise absent from the tips of the distal digit. 



None of the bones of the pelvic extremity in Conurus have air 

 admitted to their interiors, and they all become dark and greasy in 

 the ordinarily pre])ared skeleton. This is likewise the case in Cacatua 

 and other Psittaci. 



'\\\^ femur has a large, semiglobular head, with a shallow, though 



