XVIII. Notes on a Carboniferous Selachian Fish from the Cement-limestone Series of East Kilbride

Abstract

The genus Cochliodus was established by Professor Agassiz, in 1838, for some peculiar shell-like palatal teeth found in the Carboniferous limestone series, five species being named by him— Cochliodus acutus, C. contortus, C. magnus, C. oblongus , and C. striatus ; but it has since been doubted whether some of these do not rather belong to some closely allied genus. Thus Prof. M'Coy, speaking of C. magnus , at page 623 of his “Palaeozoic Fossils,” says, “This species varies considerably in the outline of the different specimens, and I think it is very doubtful whether it is truly of the genus, on account of the flatness and slight inrollment of the teeth, and the little definition of the characteristic oblique ridges; the strong crenulation of the margin is also a character which I do not recollect to have seen in Cochliodus , but recalls the observation of Capt. Jones, (in Portk. Geol. Bep.) that the Cochliodus magnus , he thinks, pass into the Helodus planus , which may be borne out by a large suite of specimens, although I have not yet myself seen the passage.” I am glad to be able to exhibit to the Society a specimen of this fish, which seems to confirm in a measure the truth of Captain Jones' conjecture, as stated by M'Coy. This fine, I might almost say unique, specimen was discovered this autumn by my friend Mr. Andrew Paton, of East Kilbride, in the cement-limestone series, and he has kindly placed it in my hands for exhibition. The specimen This 250-word extract was created in the absence of an abstract