XIII.—A New Cephalaspid Fish from the Downtonian of Scotland, with Notes on the Structure and Classification of Ostracoderms

Abstract

Fossils have been known to occur in the early “post-Caledonian” sediments of Cowie Harbour, Stonehaven, for more than sixty years. Dr R. Campbell (1911, 1912 a, b, 1913) gave an account of the stratigraphy and recorded a number of fossils, including plant-fragments, arthropods (subsequently discussed by Steamer, 1934, 1935), and fishes (Traquair, 1912; Kiaer and Heintz, 1932 a; Heintz, 1939). The fossinferous “Dictyocaris-band,” exposed on the tidal foreshore, has been visited repeatedly by members of this department, who have collected a considerable quantity of fragmentary remains. During the last few years interesting new forms have been obtained by Dr F. H. Stewart, by the writer, and by senior and research students. Faunal lists and a discussion of the age of the beds occur later in this paper. The Dictyocaris-band outcrops also in the Tewel Burn. A cephalaspid scale from this section (Geol. Surv. Scot., T. 2738c and T. 2739c) is described below.