IGUANODON PEESTWICHII PKOM THE XIMMElllDGE CLAY. 433 



34. Iguanodon PpvEstwichii, a new Sjjecies from the Kimmeridge 

 Clay, distinguisJied from I. Mantelli of the Wealclen Formation 

 in the S.E. of England and Isle of Wight hy Differences in the- 

 Shape of the Vertebral Centra, hy fewer than five Sacral Verte^ 

 hrce, hy the simpler Character of its Tooth-serrature, c^*c., 

 founded on numerous fossil remains lately discovered at CuMi>roE, 

 near Oxford. By J. W. Hulke, Esq., E.E.S., F.G.S. (Eead 

 April 28, 1880.) 



[Plates XVIII.-XX.] 



These fossils, which Mr. Prestwich has kindly given me an 

 opportunity of studying, are, for the extent of information they 

 convey of nearly every part of the skeleton, the most important 

 Tguanodont remains yet discovared at any one time in this country. 

 The only others that may vie with them are those in the well-known 

 Mantellian Maidstone block, in the British Museum, and some, 

 said to represent the greater part of a skeleton, reported to have 

 been found several years since at Hastings, preserved in a private 

 collection, inaccessible, which in their entirety have not, so far as I 

 can learn, ever been examined by an anatomist. 



The Cumnor fossils appear to have formed part of one skeleton. 

 They represent an animal between 10 and 12 feet long, which had 

 not reached maturity. Its head was lizard-like, with large eyes 

 and capacious nostrils. Its neck was very flexible and moderately 

 long. Its trunk, particularly the thoracic region, was long, and 

 borne on stout clawed limbs, of which the hinder were much stouter 

 than the fore. The tail, of considerable length, tapered very gradu- 

 ally ; and for more than half its length it was flattened laterally. 



Unfortunately, as too frequently happens, the removal of the 

 fossils by the unskilful hands of day-labourers has occasioned 

 much damage and many losses. The bones had been already much 

 crushed by the pressure of the beds ; but many of the fractures are 

 plainly quite recent. These injuries are not, however, without 

 some compensating circumstances ; for the broken surfaces afford in 

 several instances an insight into structural details which may not 

 be so well perceived in an entire bone. This is especially exem- 

 plified in the remains of the head, in which the persistence of the 

 sutures and the broken surfaces discover structural details not to 

 be seen in the skull of an old Iguanodon from Brooke, Isle of Wight, 

 which I brought under the notice of the Geological Society in 1870, 

 and which till very recently was the only fragment of an Iguanodon 

 skull which had been identified and described. Taken together, the 

 Cumnor and Brooke skulls give a nearly complete anatomy of this 

 part. The Iguanodont dentition, particularly the maxillary, has 

 never been so well shown as by these Cumnor fossils. I may 

 instance also, as matters in which they have proved highly instruc- 

 tive, the variations of the form of the articular surfaces, and also of 



Q.J.G.S. No. 143. 2g 



