IX. An account of the devonian fish, Palæospondylus Gunni, Traquair.

Abstract

The small and obscure Devonian fossil, first described by Dr. Traquair in 1890 (1), under the name of Palæospondylus Gunni , has excited a keen interest among Zoologists, owing to its asserted resemblance to the Lampreys; so that although but a short period has elapsed since its discovery, it already fills an important place in our literature. Its position in the animal kingdom has been made the subject of controversy, and is still open to discussion. Dr. Traquair, whose extensive knowledge of fossil fishes gives great weight to his opinion, concludes that “it not only appears to be, but actually is a Marsipobranch” (7); Professor Howes is no less positive and speaks of it as “an unmistakable Marsipobranch” (26); Dr. Smith Woodward, while expressing himself more cautiously, definitely includes it among Cyclostomes (4), as the sole representative of a new order, the Cyclise, a term which had been previously" proposed by Professor Gill (14), to designate a group of uncertain rank, of which palæospondylus is the only known member. In face of this agreement, an equally imposing array of authorities may be cited as bolding different views. Professors Gegenbaur (21), Wiedersheim (17), and Zittel (12), regard the claims of palæospondylus to a close alliance with Marsipobranchs as at least doubtful; Dr. Bashford-Dean, who has made a special study of recent Marsipobranchs, is even more sceptical (23), Huxley is said to have styled the fossil a “baby Coccosteus,” the late Sir J. W. Dawson (8) suggested a comparison with larval Amphibians, and Professor Graham-Kerr claims it for a Dipnoan (24).