NO. 1666. OSTEOLOGY OF CAMPT0SAVRU8—0ILM0RE. 277 



liiiul foot nearly entire. There were three functional ilisits in this foot, the 

 first being rudimentary and the fifth entirely wanting. The metatarsal of the 

 first digit is a si)lint, much curved, and with the apex above. The terminal 

 l»halanx of this digit is nuich compressed, not round as in the smaller species. 

 The second metatarsal is of much greater length. The terminal phalanx of 

 this digit is longer in proportion than that of the preceding species. The third 

 and fourth digits were large and powerful. The main dimensions of this foot 

 are as follows: 



mm. 



Length of second metatarsal 29.5 



Greatest diameter of proximal end 113 



Length of third metatarsal 345 



Greatest diameter of proximal end ' 150 



Transverse diameter of distal end 102 



Length of fourth metatarsal 1- 305 



Length of first phalanx of third digit , 140 



Length of first phalanx of second digit 120 



The remains of the present species are from a lower horizon in the Jurassic 

 than those described above, but within the limits of the Atlantosaurus beds. 



An examination of the type .specimen shows it to be a right instead 

 of a left hind foot, as originally described, and it has been so re- 

 moitnted, as shown in Plate 17, reproduced here 

 from a photograph. 



As Marsh has already pointed out, C. amplus 

 may be distinguished from the other species of 

 the genus, (1) by its great size, (2) by the 



compressed terminal j^halanx of the first digit, pj^, 3s._u n g u a l of 

 This phalanx, in nearly all of its details, re- first digit, camp- 

 sembles the ungual of the third digit of the m^rsh. Na^'mo! 

 pes in the opisthocoelian dinosaurs, as shown in yale museum, holo- 



n^ on TYPE. I NAT. SIZE. 



*'■''■ _ •«, A R T I C U L A R END. 



A second specimen. No. 1887, Yale Museum, rough outline 

 consisting of portions of the skull and lower L™™;™"r„r 

 jaws (see Plates 7*, 8, and 9), may, on account 



of its large size, be provisionally referred to this species. It was 

 collected by Prof. O. C. Marsh from deposits in the Garden of the 

 Gods, Colorado Springs, Colorado, in 1886. With this specimen 

 was found the following note in Professor Marsh's handwriting: 

 " Part of this animal and various Sauropoda bones were taken out 

 by Professor Kerr in 1878." Diligent inquiry has failed to locate 

 the repository of the parts of this specimen collected by Professor 

 Kerr, but their association with Sauropoda remains would indicate 

 the Jurassic age of the deposits in which they were originally found. 



On page 1159 of volume 2 of Nicholson and Lydekker's Manual 

 of Paleontology, they remark : " It is not improbable that the large 

 Iguanodont from the Upper Jurassic of the United States, de- 

 scribed as ' Camptosaurus amplus,' should be referred to this group 

 of Iguanodon, since it has but three functional digits in the pes." 



