444 JR. IF. Hoolei/ — Ljucuwdon manfelli — 



IV. — On the Discovery of Eemains of Iguakodon hiantelli in 

 THE Wealden Eeds OF Brighstonk Bay, Isle of Wight. 



By Eeginald W. Hooley, F.G.S. 



rilHE Iguanodon, as is well known, was discovered by jMantell, who 

 L in 1825 named it from odd teeth which had a resemblance to 

 tlie teeth of the recent Iguana. Many isolated teeth and bones were 

 subsequently found in the Wealden and Lower Greensand beds to 

 wliich the names of /. anglicum (F. Holl, 1829) and /. mantelli, 

 (H. von Meyer, 1832) were given. It was not, however, until 

 1851, when Owen described an associated group of bones on a slab of 

 sandstone from the Kentish Rag (Hythe Beds, Lower Greensand) 

 of Maidstone, Kent, w^iich had been discovered by AV. H. Bensted in 

 1834, that the genus was to any extent known. This specimen 

 has become the type of /. mantelU. In 1878 occurred tlie historic 

 discovery of the skeletons of a number of Igxmnodons in the Wealden 

 beds of Bernissart, near Mons, Belgium. 



Among these, two forms were found, a small and a large. The 

 former was identified as /. mantelli and the latter as a new species. 

 These conclusions have been generally accepted by palaeontologists, 

 but the question is reopened by the discovery of the specimen now 

 to be described. 



Description of the Specimen. — In September, 1 899, while searching 

 the clifi about 150 yards west of Cowlease Chine, Isle of Wight, 

 I discovered several pieces of bone in the debris caused by a fall in 

 the cliff. On examining that part of the cliff from which it had been 

 displaced I found many bones in situ. They were lying 8 feet above 

 the Hypsilophodon Bed near the base of the 19 feet of blue shales, with 

 Unio and Paludina in the top and Cyrena and Pahidina at the bottom, 

 as mentioned in the section given in the Geological Survey Memoirs 

 of the Isle of Wight, 1889, p. 15. On carefully removing the shale, 

 a series of eight caudal vertebrae was found lying in connexion and 

 entire, with the excej^tion of two neural spines. In addition there 

 were, anterior to these, and consecutive, two neural and one hjemal 

 spines. The combined length of the neural spine centrum and 

 ■chevron of the most anterior vertebraj (? the twelfth caudal) was 

 990mm., and covered a space 863 mm. wide. On lemoving the 

 vertebrae and clearing away the matrix I found a fine pubic bone, 

 perfect except the post-acetabular process, which had been broken off 

 in the fall of the mass. Amongst the debris many portions of bone 

 more or less fragmentary were obtained. Many of these I have been 

 able to put together, the result being the centra of four caudal 

 vertebrae, five neurapophyses and two haeraapophyses of caudal 

 vertebrae, the left ilium minus the pre-post-acetabular processes, 

 portions of the right ilium and pubic bones, the sacrum, two lumbar 

 vertebrae, and the posterior moiety of a third. 



Portions of the neural spines of the last four sacral vertebrae were 

 preserved. The penultimate and ultimate transverse processes of 

 the right side are intact, and the bases of the remaining three. On 

 the left side there is the full series of five, nearly perfect. This 



