308 Mr. H. G. Seeley on Acantliopholis platypus, 



The form of the boiies, considered by itself and in relation 

 to the other known fossil types, as well as the osteology of 

 recent crocodiles and lizards, would have led me to suspect the 

 metapodium to consist of the metacarpal bones ; yet the enor- 

 mous size of the foot-bones and small size of the caudal verte- 

 bra, and the fact, demonstrated by all other fossils, that the 

 fore foot is smaller than the hind foot, make it jyrohahh that 

 the inferences from comparison have in this case no import- 

 ance, and that the bones are metatarsal. From the shape of 

 the bones I should infer that the distal ends of the metatarsals 

 did not approximate towards each other closely, and that the 

 three inner bones and two outer bones were fasciculated. 



Another difficulty in the restoration of the foot will occur to 

 the student of Prof. Owen's writings, from the way in which 

 the foot of Iguanodon is interpreted in the Palseontographical 

 Monograph for 1857 (Wealden Rept. pt. 4). Here the Professor 

 explains the rudimentary metapodial bone as the first or inner- 

 most toe. This interpretation is so much opposed to the ana- 

 logy of recent crocodiles and lizards and fossil Pachypods, that 

 I venture to suggest that the digit which Prof. Owen has named 

 the fourth is really the first, and that which is named innermost 

 is really outermost ; and consequently the bones, instead of be- 

 longing to the right foot, would belong to the left. And to ac- 

 count for this inversion we must believe that, in extracting the 

 fossil or by some subsequent accident, the phalanges of the first 

 and third digits came to occupy each other's places, which 

 would be more credible than the interpretation which makes 

 the first Dinosamian metatarsal a mere rudiment. . Moreover 

 the proximal angles of the bones overlap each other, as in the 

 recent Reptilia ; only, if Prof. Owen's interpretation were ac- 

 cepted, they would overlap in a reverse direction to that seen 

 in Reptiles or Pachypods, the angles being directed inward^ 

 according to the figure. This alone seems to me sufficient 

 evidence of the error ; and so I would suggest to all possessors 

 x)f casts of Mr. Beckles's fossil to retranspose the phalanges of 

 the first and third digits, the present arrangement being as 

 much in defiance of osteological experience as any angel or 

 mermaid. It may not be out of place if I remark that no 

 coiToborative evidence has yet been published that the fossil 

 foot referred by Prof. Owen to Iguanodon really belongs to 

 that genus. The passage '' Not far from where the foot-bones 

 were found, the femur, tibia, and fibula of the same Iguanodon 

 were extracted — a circumstance which adds to the probability 

 of their belonging to the same limb" is obviously meant to 

 beg the question of the determination, and is not put in as 

 proof. Prof. Owen also speculates that if the claw of the 



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