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Quarterly Journal of Microscopical Science, Vol s2-76, 481-498, Copyright © 1934 by Company of Biologists
1 Demonstrator in Zoology in the University of Leeds
1. The upper jaw teeth of the larval Bel one pierce the epidermis as solid structures, unattached to the bone and afterwards become attached by the growth of their bases directly to the premaxilla. These teeth are very similar in structure to those of the larval Eel. A curious feature is shown in their development, the original dentine cone becoming clear apparently to form enamel-like substance.
2. The lower jaw and pharyngeal teeth of the larval Belone develop as hollow cones of dentine, and become attached to the bone either directly or by means of separate intermediate pediments of bone.
3. All the teeth of Salmo, Amia, Acipenser, and Polypterus are attached to the bone directly or to upgrowths more or less continuous with the bones.
4. The bony intermediate plates of the Dipnoi fuse to form the adult tooth-plate, the actual denticles disappearing.
5. The supporting pediments are shown to be only bony supports developed precociously in connexion with the teeth, and may be formed directly from the bone or separately as intermediate pediments, and are in no way different from the remainder of the bone.
6. The embryology of teeth and bone in fishes suggests that they are distinct structures, and that their close association in ontogeny and phylogeny is due to the necessity of acquiring a firm base, and not because they are parts of the same structure.