II.—Notes on Chondrosteus acipenseroides, Agassiz

Abstract

The now well-known Liassic Acipenseroid fish Chondrosteus acipenseroides was named by Agassiz in 1843, but not described by him. It subsequently formed the subject of an elaborate memoir by Sir Philip Grey-Egerton, Bart., in which, besides giving a minute account of the structure of the genus, he named two additional species—C. pachyurus and C. crassior. Putting the results of Sir Philip's investigations as briefly as possible, he maintained that while “in all essential points” Chondrosteus resembled the recent Sturgeon, nevertheless in certain others, and notably in the structure of the opercular and hyoid regions, it constituted a transitional form towards the more ordinary Ganoids. Moreover, the skin of the body presented the same naked condition seen in the recent Polyodon.