Organization of the Cy prides. Ill 
larynx. It is, however, by no means free, as supposed by 
that author, but has its larger, hinder portion united with the 
intestine. Only the smaller, anterior part, embraced laterally 
by powerful muscular bands and ventrally attached by mus- 
cular threads to the endoskeletal plate, lies free in front of 
the intestine, and is drawn forward by a large pair of muscles 
originating at the summit of the labrum and running beneath 
the brain and obliquely over the oesophagus, and backward 
by a second group of muscles acting in the opposite direction. 
This forward and backward displacement, which reminds us 
of the motory mechanism of the gizzard in the Decapoda, 
affects only the dorsal wall, the strong convexity of which 
projects into the lumen, beset with rows of pointed teeth, and 
acts like a rasp against the concave ventral wall, also densely 
armed with points. It corresponds with Zenker’s “fteibzeug,” 
while the part described by that author as u Ringknorpel ” 
represents the bottom and the lateral wall of the oesophagus. 
The middle intestine is divided by a deep constriction into two 
sections, of which the anterior surrounds the throat-like 
opening of the gizzard and gives off the two hepato-pancre- 
atic tubes into the interspace of the duplicature of the shell. 
It contains a very deep glandular epithelium, and must, as 
the stomach, have the function of digesting albuminous bodies. 
The second, far longer but equally wide section of the intes- 
tinal tube, the chyle-intestine, appears chiefly to effect the 
absorption of the nutritive materials. No muscular rectal 
section in Zenker’s sense is present ; the anal aperture is a 
narrow fissure concealed by a valve and placed dorsally from 
the furcal joints. 
5. Secretory organs . — Both the antennal gland and the 
gland of the second pair of maxillse are well developed in 
Cypris y but it is the former which is removed into the shell- 
cavity and therefore must be characterized as the shell-gland. 
Its position and form I have already represented correctly in 
my memoir on the development of Gypris (1868), but without 
tracing the finer structure. It commences above the entrance 
of the hepato-pancreatic tube into the cavity of the carapace 
and allows a terminal saccule to be distinguished from the 
gland-duct, which is somewhat tortuous, but not folded into 
convolutions. The cells of the former contain small nuclei 
and are very intensely stained by reagents. Excretory pro- 
ducts are often deposited in its lumen. The gland-duct con- 
sists only of a series of perforated cells, the nuclei of which are 
of extraordinary size and emit digitiform branches above and 
below, each representing only a single perforated cell. The 
