. An introduction to geology : intended to convey a practical knowledge of the science, and comprising the most important recent discoveries, with explanations of the facts and phenomena which serve to confirm or invalidate various geological theories. ty of the iguanodon is the fonn of its teeth,which bear a striking resemblance to the grinders of herbivorousmammalia, being evidently intended for mastication, in which respectit differs from all living animals of the lizard family. The herbivo-rous amphibia gnaw off the vegetable productions on which theyfeed, but do not chew them.— Since the
. An introduction to geology : intended to convey a practical knowledge of the science, and comprising the most important recent discoveries, with explanations of the facts and phenomena which serve to confirm or invalidate various geological theories. ty of the iguanodon is the fonn of its teeth,which bear a striking resemblance to the grinders of herbivorousmammalia, being evidently intended for mastication, in which respectit differs from all living animals of the lizard family. The herbivo-rous amphibia gnaw off the vegetable productions on which theyfeed, but do not chew them.— Since the vegetable remains, saysMr. Mantell, with which theteetb of the iguanodon are associated,consist principally of those tribes of plants that are furnished withrough thick stems, and which were probably the principal food ofthe original animal, we may be permitted to remark, that this pecu-liar structure of the teeth seems to have been required, to enablethe animal to accommodate itself to the condition in which it wasplaced.—The iguanodon appears also to have possessed a horn,equal in size to that of the rhinoceros, and not very different fromit, in form : in this respect, it resembles a living species of iguana,a native of St. Domingo. d c b. a. h. c. represent the teeth of the iguanodon of the natural size ;a is the front view of the perfect tooth of a young animal; b is thefront view of a full grown tooth, with the points worn down; c, theback view of the tooth ; c?, represents a highly magnified tooth of theliving iguana. The reader may be surprised at the smallness of theteeth of the iguanodon ; but the same proportion takes place in theteeth of all reptiles. A living iguana, five feet in lengili, has teethnot larger than those of a mouse, e, is a reduced drawing of the horn. One of the thigh bones of ihe iguanodon, in Mr. Mantells muse-um, is twenty three inches in circumference. The condyle, or jointof another bone which I measured, was thirty four inches in circum- 19
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Keywords: ., bookcentury1800, bookidintroduc, booksubjectgeology, bookyear1833
