OF THE SCAPULA IN THE BATRACHIA. 209 



cartilage ; superfici.il articulation and fovea acetabulum strongly 

 marked. 



Example. 



Length of prsecoracoid (greatest) 10 units. 



,, scapula (upper border) 10*7 ,, 



„ (lower „ ) 12-2 „ 



„ „ shaft 7-9 „ 



Breadth of ,, (distal end) 7'9 ,, 



» n (middle) 36 „ 



,, pars acromialis 4'3 ,, 



,, pars glevoidalis 2*15 ,, 



Length of supra-scapula 12"8 ,, 



In the following species the scapula is like that of B. vul- 

 garis : — B. ha'inaiiticus Cope, B. calamita Laur., B. viridis Laur., 

 B. intermedins Gthr., B. lentiginosus Shaw, B. marinus L., B. 

 crucifer Wied. 



In B. latifrons Blgr., B. tuberosus Gthr., B. melanostictus 

 Schn., B. claviger Ptrs., B. quadriporcatus Blgr., B. typhonius L., 

 and B. valliceps Wiegm., the scapula is a little longer than the 

 prsecoracoid, but of the same form as that of B. vulgaris. 



In B. granulosus Spix the scapula is a little shorter than the 

 prpecoracoid. 



There is remarkably little variation in this genus, in some 

 species the pars glenoidalis is somewhat shorter than in others, 

 and there is slight variation in the length of the shaft. 



Example to show Range of Variation in Bufo. 



B. granulosus. B. melanostictus. 



Length of proscoracoid 10 units. 10 units. 



,, scapula (lower border) . 7*7 ,, 14 - 2 ,, 



„ shaft 6-2 „ 10 „ 



Breadth of „ (distal end) ... 6-2 „ 7-1 „ 



„ ,, (middle) 3*3 „ 3 „ 



,, pars acromialis 4 - 6 ,, 3 ,, 



,, pars glenoidalis 3 # 3 ,, 3 ,, 



Length of supra-scapula 10 - 4 „ 14 - 3 ,, 



B. melanostictus has been chosen as an example of the more 

 developed type of scapula, as, being a common Malayan form, it 

 forms an interesting comparison with B. granulosus from 

 E. South America. 



The equal development of the pars acromialis and pars 

 glenoidalis in length, together with the fact that the latter is 

 always widely separated from the coracoid by cartilage, dis- 

 tinguishes the scapula of Bufo from nearly all other genera of the 

 Arcifera, (see text-fig. 1 ). 



Rhinophryxus D. & B. 



2i. dorsalis D. & B. — Scapula as in Bufo. 



