XXVI. The Vertebrate Animals of the Coal Period

Abstract

Dr. Traquair stated that the vertebrate fauna of the Coal period was confined to fishes and amphibia, no remains of reptiles, birds or mammals having yet been discovered in Carboniferous rocks. The fishes belonged mostly to groups which are scantily represented, or nearly extinct at the present day. Abundant selachian or shark remains had been found, chiefly as scattered teeth and spines, so that it was difficult to form an idea of the special affinities of the creatures when entire. No doubt could, however, be entertained of the affinity of some of the Carboniferous sharks to the recent Notidanids, and of others to the Cestracionts or “Port Jackson sharks,” while two orders, one of which contained the singular genus Pleuracanthus , and the other the problematic Acanthodians, were entirely extinct. Of Teleostomous fishes, the group of Crossopterygii, now reduced to the African genera, Polypterus and Calamoichthys , was abundantly represented by the extinct families of Osteolepidae, Rhizodontidae and Cœlacanthidae, some of which, as Rhizodus , attained a great size. The “lung fishes,” now reduced to three genera, Ceratodus, Lepidosvren , and Protopterus , were represented in Carboniferous times by Uronemus ; Ctenodus and Sagenodus . The sturgeon-like fishes, now nearly extinct and reduced to a few degenerate forms, were abundantly represented in Carboniferous waters by the long-extinct families of Palaeoniscidse and Platysomidae. The former consisted of elegant fishes shaped something like a modern roach or trout, but having rhombic ganoid scales often beautifully sculptured, and heterocercal tails. The latter family seemed to be a specialised offshoot from This 250-word extract was created in the absence of an abstract