338 



THE GEOLOGIST. 



The remains of Iguanodon were discovered in 1834, after the blast- 

 ing of one of the layers. The bore being placed in the middle of a 

 rise or mound in tlie stone, the separation of the mass was so com- 

 plete, that some parts were thrown by the force of the powder to a 

 considerable distance, and a mouth elapsed before I could fit the 

 fragments together in their relative places. Fortunately there was 

 no interveniDg piece lost ; and the mass, as shown in the drawing, was 

 completely put together. It is probable, however, that more of the 

 skeleton had been embedded in the surrounding stone, and had been 

 removed by the workmen previous to the blasting out of the portion 

 preserved. This is the more likely, as I took every precaution to 

 search what remained of the bed in every direction around the spot 

 where it was found for some time afterwards, but without success. 



I then constructed a shed to cover the specimen, and set to work 

 to chisel away the stone covering over the bones. As the enormous 

 proportions of the femur became developed, the interest of the work 

 increased in a great degree ; and not having any one near me suffi- 

 ciently acquainted with comparative anatomy to help me to a know- 

 ledge of the structure of this novelty, and finding the characters of 

 the bones to differ so widely from any drawings I could get access to, 

 I acquainted Dr. Mantell with my discovery. From the plates in his 

 excellent work, ' The Geology of the South-East of England,' I formed 

 the opinion that my specimen was a large portion of the skeleton of 

 the great herbivorous reptile, the Iguanodon — an opinion the Doc- 

 tor concurred in when shortly afterwards he inspected the specimen. 



The bones thus obtained consisted of two thigh-bones, each 33 

 inches long; a leg bone (tibia), 30 inches ; a chevron-bone, or one of 

 the inferior processes of the tail, 12 inches ; the metatarsal and pha- 

 langeal bones of the hind feet; two claw-bones (unguical phalanges), 

 which were covered by the nail and claw ; two fingers or metacarpal 

 bones of the fore-feet, 14 inches ; a radius ; several dorsal and caudal 

 vertebrae ; fragments of several ribs ; the two clavicles ; and two large 

 flat bones, apparently parts of the pelvis. 



The next bed below the Iguanodon strata is the " MoUuskite Has- 

 sock," — a layer of hassock containing an immense accumulation of dead 

 sliells, drifted wood, and a great quantity of round masses of a dark 

 animal substance. The shells are chiefly those of Trigonia alceformis, 

 but Nautilus elegans is of frequent occurrence ; and by judicious 

 cleavage of the layer, most interesting groups of fossils are obtained. 

 The brown masses of animal matter or molluskite is chiefly contained 

 within the cavities of the shells, with whose white shell-substance it 

 strangely contrasts. A fino specimen of a sauroid tooth was found by 

 me in this stratum, and presented by me to Professor Owen, who 

 named it PoJgptgcliodon contimms, and favoured me witli the follow- 

 ing observations upon it : — " The tooth belongs to one of the largest 

 and one of the rarest of the extinct gigantic marine Saurians, cha- 

 racteristic of the chalk and greensand formations. Some enormous 

 bones of tlie Polypi gcliodon were discovered in a greensand quarry at 

 Hythe, and were presented by H. B. Mackeson, Esq., to the British 



