On the Dentition of Lepidotus maximus , Wagner, as illustrated by Specimens from the Kimeridge Clay of Shotover Hill, near Oxford

Abstract

The specimens upon which this paper is founded were obtained by one of us (Mr. Henry Willett) from the Kimeridge Clay of Shotover Hill, and at no great distance from each other, although at different times—two in the spring and one in the autumn of 1887, and the fourth in the spring 1888. The size and perfection of these specimens are alone sufficient to warrant their being brought under the notice of the Society; but, besides this, one of them appears to represent a distinct species, probably new to England, if not also to the Kimeridgian fauna of France. The species of Lepidotus known in England are as follows:— Section L eptoganoidei Suborder L epdosteoidei The Lepidosteoid Fishes range from the Permian to the present day. They are represented in the Permian rocks by the genus Acentrophorus . The following genera range through the British Secondary rocks:c Many species of Lepidotus attain a large size. Lepidotus maximus , Wagn. (= Sphœrodus gigas , Ag.), from the Lithographic Stone of Solenhofen in Bavaria, measures over 5 feet in length and 2 feet in depth of body; while L. Mantelli , Ag., from the Wealden Series (Hastings Sand) is nearly, if not quite, of equal dimensions. The similarity of the teeth in Sphœrodus and in the larger species of Lepidotus (such as L. maximus ) induced Agassiz to abolish the latter genus (but with hesitation) in 1869. Prof. Owen, however, from the microscopic structure of the teeth, regarded the two genera as distinct. On the other hand, many continental palæontologists