338 
THE GEOLOGIST. 
The remains of Iguanodon were discoYered in 1834, after the blast- 
ing of one of the layers. The bore being placed in the middle of a 
rise or mound in the 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 month elapsed before I could fit the 
fragments together in their relative places. Fortunately there was 
no intervening 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 difter so widely from any drawings I could get access to, 
I acquainted Dr. Mantell with my discovery. Erom 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 " Molluskite Has- 
sock," — a layer of hassock containing an immenseaccumulationof dead 
shells, drifted wood, and a great quantity of round m.asses of a dark 
animal substance. The shells are chiefly those of Trigonia alcsformis, 
but Nautilus eJegans 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 fine specimen of a sauroid tooth was found by 
me in this stratum, and presented by me to Professor Owen, who 
named it Polyptyclwdon continuics, and favoured me with 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 the JPolyptycliodon were discovered in a greensand quarry at 
Hythe, and were presented by H. B. Mackeson, Esq., to the British 
