1899.] AMBEIOAN SPADE-rOOT. 795 



Vertebral column twice as long as the skull. Vertebrte pro- 

 coelous ; neural arches covering each other, with a low crest and a 

 short posterior process ; the three anterior diapophyses long, the 

 first dii-ected forwards, the second horizontal, the third directed 

 backwards ; the following diapophyses short, the sixth and seventh 

 slightly oblique, directed forwards. Sacral vertebra with strongly 

 dilated diapophyses, which are subtriangular and a little broader 

 than long. IJrostjle as long as the seven anterior vertebrae and 

 fused with the sacral. 



Coracoids and prsecoracoids strongly curved, connected by an 

 arched cartilage ; prsecoracoid not entering glenoid cavity ; no 

 omosternum ; sternum a large cartilaginous plate. Supra- 

 scapular nearly entirely ossified. Humerus once and a half as long 

 as radius-ixlna. Seven bones in carpus, three in contact with 

 radius-ulna ; two bones to the pollex. 



Pelvis three-fourths the length of the vertebral column. Pubis 

 cartilaginous. Femur feebly curved, longer than tibia, which is 

 twice as long as astragalus and calcaneum. Three small bones in 

 second rovy of tarsus, and a very large praehallux formed of two 

 bones. Distal phalanges obtuse. 



milliru. 



Length of skull 20 



Breadth „ . 26 



Vertebral column 41 



Humerus 18 



Eadius-ulna 12 



Manus 14 



Pelvis 30 



Femur 24 



Tibia 20 



Tarsus 10 



Pes 22 



The result of this examination of the osteological characters is 

 that, as pointed out by Gill, Cope was quite mistaken in placing 

 Scapliiopus together with Pelobates in a group opposed to that 

 containing Pelodytes. In spite of a certain resemblance due to 

 convergence through similarity in their mode of life, Scaphiopus 

 shows no very near affinity to Pelobates, and the relation of the 

 latter to Pelodytes is unquestionably much closer. On the other 

 hand, the propriety of uniting the three genera in one natural 

 group (Pelobatidce) is fully confirmed, as are, in fact, most of 

 the groupings into higher groups proposed by the illustrious 

 American naturalist in dealing with the classification of the 

 Tailless Batrachians in 1865. 



EXPLiJSTATION OF PLATE LU. 



Scaphiopm soUtarius, drawn from life in three attitudes. 



