AND AVES OF NORTH AMERICA. 71 



Measurements of Vertebra. 

 Of Young. 

 Eighth? dorsal; total length, 



length to shoulder, 



longitudinal line between zygapophyses, 

 horizontal base of neural spine, 

 depth of neural canal, 

 " " articular cup, 

 width of " " 



neural suture to nearest diapophysis, 

 Thiid? lumbar; total length, 



length to shoulder, 



longitud. line between zygapophyses, 

 horizontal base of neural spine, 

 depth neural canal, 

 " articular cup, 

 width " " 



First sacral ; length, 



anterior width centrum, 

 posterior " " 



depth neural canal, 



" articulation of diapophysis, 

 length " " 



width neural arch between diapophyses, 

 Anterior caudal ; length, 



" to shoulder, 

 depth neural canal, 

 " articular cup, 

 width " " 



width inferior plane, 

 Distal caudal ; length, 



" to shoulder, 

 depth cup,* 

 width " 

 length base diapophysis, 



None of the vertebra exhibit a constriction of the neural canal by a ridge on each of its sides, as is seen in the H. 

 tenebrosus. 



This specimen is named from the short longitudinal and vertical extent of its hypapophyses. 



A right humerus accompanying three vertebras of the adult, has the same color and mineralization, and was 

 found with them ; it probably belongs to the same animal. Compared with a humerus of H. obscurus of medium 

 size, it is three-fifths the length and has more strongly marked articular faces. The head is more transverse, less 

 rounded, and more strongly divided into the scapular and coracoid faces. The width of the head is one-fourth the 

 length, and reaches the summit of the deltoid crest. This crest is lower down in H. obscurus, the above width only 

 reaching its proximal base. The anterior face above the crest is concave in H. brevispinis, nearly flat in H. obscurus. 

 There is a moderate internal tuberosity distally, and the condyles are moderately prominent. Coronoid fossa well 

 marked. 



* Heasuremeuts of the articular cup are always made from middle to middle of the rim. 



In. 



Lin. 



1 



5. 



1 



1. 



1 



5.5 





11. 





4.5 





0.5 





9.5 





3. 



1 



5. 



1 



1. 



1 



6. 



1 







4.75 





9. 





11. 



1 



2.75 



1 



.75 





10. 





4.75 





11. 





9. 



1 



2.5 



1 



5. 



1 



1.5 





4.5 





8. 





8.75 





4. 



1 



5.5 



1 



3.25 





6. 





5. 





3.75 



