Open AccessThe anatomy and phylogeny of spondylus, with a particular reference to the Lamellibranch nervous system
Author(s) -
William J. Dakin
Publication year - 1928
Publication title -
proceedings of the royal society of london. series b, containing papers of a biological character
Language(s) - English
Resource type - Journals
eISSN - 2053-9185
pISSN - 0950-1193
DOI - 10.1098/rspb.1928.0046
Subject(s) - biology , genus , invertebrate , anatomy , pecten maximus , zoology , paleontology , ecology , mollusca , bivalvia
A study of the anatomy of the rather rare LamellibranchSpondylus , has always attracted the author, owing to the fact that at a comparatively early date the striking resemblance between the eyes of this creature and the remarkable eyes of the genuspecten been noted. In structure the eyes ofpecten stand practically alone amongst invertebrate visual organs, and since, by reason of their complexity as well as number, their evolution has been associated with the faculty of swimming, it was a matter of considerable interest to determine the relationships ofPecten withSpondylus for whilstpecten can swim,Spondylus lives attached to rocks. The investigation was made purely from the above view-point, and hence minute details of histology, etc., have not been given. Resemblances toPecten were expected. One very unexpected morphological anomaly turned up, however; and in the midst of a remarkable agreement with the genusPecten , one system, the nervous system, presented a condition altogether unique amongst Lamellibranchs. To obviate repetition, reference should be made to an account of the anatomy of the genusPecten by the author (Dakin, 1909) and also to a paper, following this, which deals with the eye.