On the Internal Organisation of Cumaeea. 
(PI. LXV—LXVIII). 
To show more clearly the relation of the Cumaeea to other Crustacea, 
I propose in the following pages to give a short account of the internal organs 
in this peculiar group. These investigations were made many years ago, chiefly 
by the examination of fresh specimens, and only a few additions and corrections 
have recently been supplied. In order to get a general view of the internal organs 
in their natural situation, it is necessary to select some more pellucid forms, and 
to examine them, while still alive, under the microscope,' applying transmitted 
light. Several of the organs may thus be at once observed, whereas other 
organs are less distinctly traced, owing to the imperfect pellucidity of the 
integuments. In every case a close examination of the organs cannot be accom¬ 
plished without dissection. This should, if possible, be performed on fresh speci¬ 
mens, immediately after they have been killed, as a dissection of specimens 
preserved for a long time in alcohol or other preserving fluids, always gives 
far less satisfactory results as regards this part of the anatomy. An attempt 
to make sections of alcoholic specimens, after applying the usual staining and 
imbedding method, was not successful, probably owing to the difficulty with which 
the integuments are permeated by the melted paraffin. 
1. Intestinal System. 
The intestinal tract (see PI. LXV—LXVIII, fig. 1) commences with a 
very short muscular cesophagus (PI. LXV, fig. 2, oes), which ascends almost 
perpendicularly from the mouth to the stomachal part of'the intestine (s t), and 
is marked off from the latter inside by 2 projecting lips. The stomachal part forms 
a considerable dilation, which extends through the part of the body covered by 
the carapace, curving at the hindmost limit of this part abruptly downwards, and 
13 — Crustacea. 
