Notes on the Inshore Plankton of Plymouth

Abstract

During the years 1940–5 plankton samples were examined regularly from inside the Plymouth Breakwater, with the exception of a few months. Although it was not possible to do any quantitative work, special attention was given to larval forms, especially of the decapods, molluscs and annelids. The presence of these larvae gave a good idea of the breeding seasons of the various species. As it is only recently that many of these larvae have been identified, this is the first time that detailed specific notes have been made of their presence; and it is thought to be worth while to publish these results. To help those who wish to identify the larvae, a reference to a description of each species is given whenever possible, in square brackets after its name. It should be clearly understood that the absence of any species from these notes does not necessarily imply that it might not have been there, although all the samples were carefully examined. Most of the Coelenterates, the Cirripedia, Copepoda, and young fishes, are omitted here. Of the remaining ingredients of the plankton, various records were kept; and the occurrence of the more noteworthy of these forms, according to months, is shown in Table I.