Magazine of Natural History and Journal of Zoology, Botany, Mineralogy, Geology and Meteorology (Volume 4 ) (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated.1840 Excerpt: ... Coralline crag, Ramsholt and Sutton. I propose to give the generic name Pleurodon, to a small coralline-crag shell, which it seems to me cannot properly be referred to any genus hitherto established. The Nucula miliaris of M. Deshayes, if not specifically identical with this shell, must be closely allied to it; and in placing the French fossil in the genus Nucula, M. Deshayes has expressed a doubt as to the correctness of his determination, in consequence of the existence of the lateral tooth. The affinities of Pleurodon, as indicated by the shell alone, probably justify its being placed with the Arcacea; though its precise position in that family cannot be determined in the absence of a knowledge of the animal. At Ramsholt the valves are generally found united, the large prominent teeth retaining them in apposition. I have given as a synonyme the above name of Deshayes, presuming his Nucula miliaris may be the same shell, but I am unable to discover the internal pit for the ligament he speaks of, and which his figure so conspicuously displays. The crag specimens have a depression placed externally to the teeth on the shorter side, where I imagine the ligament to have been situated. Deshaye's figure shows seven teeth, whilst the shells from the crag never display more than six, and seldom more than five. Arca Noa, Auct. PI. xiii. fig. 2 and 2 a. Red crag Sutton, fig. 2. Coralline crag, Sutton, fig. 2 a. I feel unwilling to give a new name to this shell, since a very scrupulous examination inclines me to the belief of its not being specifically different from a well-known British species, although it was a matter of some difficulty to satisfy myself on this point. My crag specimens vary much, as do also the recent shells: a young one of the latter in my poss...