V.—On Some Points in the Anatomy and Habits of the Lophogastrid Crustacea

Abstract

In the following pages two separate subjects are considered which are connected only by their relation to the same animals. The first concerns the feeding mechanisms and habits of the Lophogastridæ, but unfortunately no living animals could be examined. As a result of some work on the feeding mechanisms of the Malacostraca (Cannon and Manton, 1927, in the press, etc.) it was concluded that in the Syncarida, Peracarida, and Eucarida a primary filter-feeding habit exists. This has been modified or given up entirely in the higher forms of each division in favour of feeding on larger masses of food. In the adult Hemimysis, Anaspides , and Nyctiphanes the filter-feeding mechanisms are essentially similar. The maxilla forms a combined suction pump and filter and draws a current of water through a filtering comb of setæ borne on its proximal endite. This comb is scraped by the basal part of the first trunk limb, which transfers the collected food forwards on to the proximal endite of the maxillule by which it is pushed into the mouth.