404 DR. A. FARRE ON THE STRUCTURE OF THE Cl LI OB RAC HI ATE POLYPI. 
remains suspended from the upper part of it by the intestine, which appears to have 
some attachment at this point. The upper part of the tube, however, is generally 
brought down lower than the stomach, in order that the tentacles may be completely 
drawn in (fig. 3. c.). By this suspension of the stomach from the upper part of the 
cell a fixed point is obtained, from which the retracted flexed portion of the tube may 
erect itself with the same effect as if the stomach were in contact with the bottom of 
the cell. This is a point which it would be important to observe in generic distinc- 
tions ; but here, as with many other points in this species, my observations were not 
carried to the extent that they have been in others, as this was one of the specimens 
with which my investigations were commenced, and I have never since had an oppor- 
tunity of confirming them. This is the more to be regretted, as from the complete 
isolation of the cells, and the extreme transparency of their parietes, a clearer view 
of their contents is obtained than in any species that I have subsequently met with. 
The spots upon the pharynx, and their absence in the triangular ciliated space, were 
remarkably distinct (fig. 3. a 1.), as was also the difference between the dark brown 
colour of the hepatic follicles in the replenished stomachs, and their pale and almost 
inconspicuous character in the empty ones. (Compare a and h. fig. 3.) The position 
of the cardia was not ascertained. When the body was turned so that the pylorus 
was presented to view, and this happened to be empty, a row of cilia were distinctly 
seen surrounding it. The vibration of these cilia, as well as of others which were 
observed in the stomach, appeared to be entirely under the control of the animal. 
Their action was frequently observed to be suddenly suspended, when the rotation of 
particles ceased also, and when it recommenced the motion of particles was renewed. 
This rotation was often so rapid at the pylorus that I should think from one to two 
hundred revolutions must have been performed in the minute. When very small 
animalcules were introduced into the bulging pharynx, several convulsive efforts were 
sometimes made before they could be swallowed ; during these the animalcules not 
unfrequently escaped again by the mouth, but were intercepted by one of the ten- 
tacula being bent forward and striking the animalcule as it rose with a sharp blow 
that drove it back again into the pharynx. The animalcules did not immediately 
perish in the stomach, but continued their motions for some time after being intro- 
duced into it. 
The gastric and tentacular retractors are particularly distinct, and have the usual 
origins and insertions (fig. 3. d 1 and 2.). The double row of parietal muscles (fig. 3. 
d 3.) have been already described in the notes on the species first quoted. There ap- 
pears to be but one set of retractors of the operculum (fig. 3. d 4.), which is generally 
drawn towards the side of the cell from which they arise, leaving a slight indentation 
in the top of the latter when retracted (fig. 3. c.). The granules on the parietes are 
less numerous than in most instances, but very conspicuous. 
The cells have an oblong form, and are connected to their narrow creeping stem 
by a short peduncle. The opercular portion terminates in a notched margin, and is 
