IGUANODONTIDiE. 



195 



From its superior size the following specimen may indicate a 

 distinct species. 



R. 167. A left femur, imperfect at the extremities. 



Genus IGUANODON, Mantell \ 



Including Cumnoria, Seeley 2 . 



Premaxilla edentulous ; maxillary and mandibular teeth (fig. 37) 

 with marginal and sometimes lateral serrations; orbits (fig. 41) 

 irregular, and apparently no sclerotic ossifications. Cervical, and 

 apparently the first dorsal, vertebras opisthoccelous ; the others 



Fi- 37. 



Iguanodon, sp. — Lateral (A) and profile (B) views of a lower tooth ; from 

 the English Wealden. \. 



amphiccelous ; sacrals either compressed or inferiorly flattened, four 

 to five in number. Manus with first digit modified into a conical 

 spine. Ilium (figs. 39 & 46) with long preacetabular process, and 

 postacetabular portion either rounded or pointed posteriorly ; ischium 

 in some instances longer than slender pubis. Femur longer than 

 tibia ; three digits in pes, with short and stout metatarsals and 

 phalangeals, the terminal joints being very broad and depressed. 



a. Proiguanodont Group. 



Anterior dorsal vertebras with arches moderately or very tall, and 

 centra of these and middle dorsals less compressed and more wedge- 



1 Phil. Trans. 1825, p. 184. 



2 Kep. Brit. Assoc, for 1887, p. 698 (1888). 



o2 



