Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 2.djvu/61

A double row of similar hooks occurs on the first dorsal ray of the Barbel, (Barbus Vulgaris.) And on the anterior ray both of the dorsal and anal fins of the Carp, (Cyprinus Carpio.)

Fig. 4. Transverse Section of fig. 3, at a.^[1] (De la Beche.)

Plate 27e. V. I. p. 220.

Fig 1. Portion of the palatal teeth of Acrodus nobilis, resembling a cluster of contracted Leeches. These teeth are in their natural place, adhering to the curved granular bone of the palate, which is well preserved, and impregnated with Carbonate of lime. (Miss S. C. Burgon. Original.)

Fig. 2. Continuation of the three rows of teeth on the reverse of fig. 1. Scale one half. (Original.)

Fig. 3. One of the largest teeth on the centre row, having the upper part of the Enamel worn away by friction. Nat. size. (Original.)

Fig. 4. Magnified view of the minute tubercles of Enamel which grew upon the skin; the decay of the skin

1. In the Lond. and Edin. Phil. Mag. Jan. 1836, the author has published a notice of his recent discovery of the jaws of four extinct species of fossil fishes of the genus Chimæra, a genus hitherto unknown in a fossil state. The only known species (C. monstrosa) approximates most nearly to the family of Sharks; and is found pursuing Herrings and other migratory fishes. The Chimæra is one of the most remarkable among living fishes, as a link in the family of Chondropterygians; and the discovery of a similar link, in the geological epochs of the Oolitic and Cretaceous formations, shows that the duration of this curious genus has extended through a greater range of geological epochs, than that of any other genus of fishes yet ascertained by Professor Agassiz, and leads to important considerations in Physiology.

   The Chimæra partakes of one remarkable character with the Cestracion Phillippi, whereby this species alone, among living Sharks, is connected with the extinct forms of that family, in having the first ray of the dorsal fin enlarged into a strong bony spine armed with sharp hooks, like the Ichthyodorulite of the earliest fossil Sharks.