OSTEOLOGIA AVIUM. 



[PsiTTACUTtf!. 



Sternum longer in proportion to its width than in P erythacus ; the remaining bones 

 similar except in measurements. 



Measurements. 



Tenths. 



Length of humerus 13 



Length of ulna . 16 



Length of metacarpus 10 



Length of femur 12^ 



Length of tibia 18 



Length of metatarsus 6J 



Length of sternum . . -. . . . 20 



Tenths. 

 Breadth of posterior margin of sternum 8 \ 

 Breadth of anterior margin of sternum 8 



Depth of keel 7 



Length of head 22 



Breadth of head 11^ 



Length of pelvis . . j . . . 20 

 Breadth of pelvis 9 



Psittacus, Linn. 



Albifrons, Sparm. 



Psittacus, Linn. 



Leucocephalus, Linn. 

 I have the sterna, coracoids, furcula, and scapula? of the above two birds ; they 

 resemble in every respect those of the two last-mentioned species. 



Psittacus, Linn. 



Guildingii, Vig. 

 Foramina on the posterior margin of the sternum nearly obliterated ; in other respects 

 similar to P. erythacus, in the British Museum. 



Measurements. 



Tenths. 

 Breadth of posterior margin of sternum 16 

 Breadth of anterior margin of sternum 12 



Tenths. 



Length of humerus ...... 27 J 



Length of ulna ....... 31 



Length of metacarpus 18 



Length of femur 21 



Length of tibia 38|- 



Length of metatarsus 9 



Length of sternum 27 



Depth of keel 7 



Length of head 27^ 



Breadth of head .25 



Length of pelvis .33 



Breadth of pelvis 15 



Chrysotis, Sw. 



Ochrocephalus, Gm. 

 Very similar to Psittacus, but with the pelvis narrower ; the bony ring round the 

 orbits not quite perfect ; the sternum not so much rounded on its posterior margin, and 

 the lateral margins not so much constricted behind the junction of the ribs. 

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