« 800 GEOLOGICAL SURVEY OF THE TERRITORIES. 
PLATE XXII. 
Fig. 114.—The three last cervical vertebrae from Cathartes aura, seen from below, 
showing the formation of the cervical pleurapophyses from the processes of these 
vertebra by gradual metamorphosis as the bird passes from young to maturity; speci- 
men size of life. cy, ribs that remain free in the adult and after the change just re- 
ferred to is complete. 
Fre. 115.—Hyoid arch of the same bird. 
. Fre. 116.—Left lateral view of the skull of Gyparchus papa; size of life. 
Fra. 117.—Superior aspect of pelvis of Cathartes aura, life size; caudal vertebra 
still in situ. 
