CRETACEOUS REPTILES OF THE UNITED STATES. 71 
of 1858 in the pleasant little village of Haddonfield, Camden county, New 
Jersey, was informed by a neighbor, Mr. J. E. Hopkins, that som2 remarkable 
bones of huge size had been discovered while digging marl upon his farm about 
twenty years previously. The specimens first found had been all given away 
or lost. Under the expectation of finding others, Mr. Foulke employed men 
to dig in the position of the old excavation, which was in a ravine through 
which flowed a branch of Cooper’s creek. At the depth of nine feet numerous 
bones were found in a bed of tenacious blue clay, mingled with a multitude of 
fossil shells. The bones, though fractured, were otherwise well preserved, and 
exhibited no appearance of being water-rolled. Indeed, the most delicate of the 
accompanying shells, though decomposed, had preserved their forms so per- 
fectly that it was evident the animal remains had originally rested on the soft 
mud at the bottom cf a quiet sea. The bones which were obtained consisted 
of twenty-eight vertebra, part of the pelvis, most of the bones of the left fore 
and hinder extremities, some small fragments of jaws, and nine teeth. 
The vertebrze of the neck and forepart of the dorsal region have their bodies 
convex in front and concave behind, the reverse of the condition in the living 
crocodiles, and in the extinct Mosasaurus. The degree of convexity and con- 
cavity declines in the posterior dorsal vertebra, and in the vertebree of the loins 
and tail the bodies are biconcave. The anterior caudal vertebree are the largest 
of the spinal column, though not so long as most of the others. A perfect speci- 
men indicates the tail to have been of enormous size—near the root about a foot 
and a half in vertical diameter, and eight inches transversely. The humerus or 
arm: bone is twenty-two and a half inches long, and nearly seven inches broad 
at the upper part. ‘The bones of the forearm have about the same length. The 
hones of the hinder extremity are especially remarkable for their huge propor- 
tions, whether viewed independently or in relation with those of the fore ex- 
tremity. The femur, or thigh-bone, is forty-one inches anda half long and 
fifteen inches in circumference near the middle. The tibia, or shin-bone, is over 
three feet long, and nearly a foot in circumference about the middle. Both the 
. humerus and femur contain large medullary cavities. 
The remains of Hadrosaurus exhibit a close relationship of the reptile with 
the Jguanodon, a lizard of equally huge proportions and like habits, discovered 
by Dr. Mantell in the next oldest formation to the cretaceous, known as the 
wealden of Europe. The specimens of the Iguanodon Mantelli now form part 
of the magnificent collection of the British Museum. 
Hadrosaurus and Iguanodon, in proportions and habits, held the same rela- 
tionship with other great extinct lizards that the bulky herbivorous pachy. 
derms do among ordinary mammals. They might be viewed as the oxen 
among the tigers, and insect eaters of lizards. 
Among living lizards, the Iguanas of South America, and the marine 
Amblyrhynchus of the Galipagos islands, are th only ones which are vege- 
table feeders, and in these the sharp, serrated teeth are only adapted to cutting 
the softer kinds, such as fruits, flowers, sea-weed, &c., and are not at all fit for 
mastication or grinding the food, 
