238 MESSRS. HANCOCK AND HOWSE 



dorsal vertebrae. But it is quite possible, indeed it is likely, 

 that they are more ribs than we have been able to enumerate, 

 in which case we have underestimated the number of the verte- 

 brae, and the two species may be found to agree in this particular 

 more closely than is apparent. It is equally impossible to ascer- 

 tain the character and 'exact number of the cervical vertebrae; 

 but as six or seven lie scattered about in front of the trunk, it 

 would seem that this species may have seven, the number of the 

 neck-vertebrae of P. Speneri, according to Meyer. All that can 

 be said about the caudal vertebrae is, that the traces of their re- 

 mains seem to indicate that the tail, when perfect, must have 

 been of considerable length. About two inches of the distal ex- 

 tremity is determinable ; and as about the same length of the 

 proximal portion seems to be broken away, the tail, when com- 

 plete, must have been longer than the trunk, which is nearly 

 three inches and a half in length. 



The ribs lie, as we have already said, spread out in their na- 

 tural order on each side of the vertebral column, and fourteen or 

 fifteen pairs can be enumerated ; but there is some difficulty in 

 determining the precise number. They are well and regularly 

 arched from end to end, and are moderately and nearly equally 

 thick throughout. Towards the proximal end they are a little 

 flattened, and terminate in a slightly enlarged simple head of a 

 triangular form. The distal extremity is abruptly truncated, but 

 is not flattened and widened to the same degree as the ribs of 

 P. Sjjeneri ; neither are the ribs so decidedly grooved as they 

 are in that species, but are on the whole more cylindrical. The 

 ventral ribs appear to have been numerous and comparatively 

 stout ; they lie pressed in between the vertebral ribs near to the 

 spinal column, but their relative number cannot be ascertained. 

 The longest vertebral ribs are near the centre of the trunk ; here 

 they are seven-eighths of an inch long measured along the chord ; 

 they shorten a little before and behind to about seven-tenths of 

 an inch in front and four-tenths behind. 



Both the coracoids are well preserved, particularly the left, 

 which lies nearly in its natural position at the left side on the 

 fore part of the trunk. The right coracoid is removed a short 



