INTRODUCTION. XX1X 
This apparatus, under a high magnifying power, is seen 
to consist of several closely packed rows of fine strong 
short hairs, very commonly arranged together in the form 
of a heart, the apex of which, directed anteriorly, is 
truncated. This appears to be the most general appear- 
ance, though in various genera it is different in form. 
Its appearance suggests its capability for triturating and 
grinding food, though it is curious that two such kinds of 
apparatus should exist at each end of the stomach, the one 
at the cesophageal entrance, the other near the pyloric 
outlet. The cavity in which the latter is placed has the 
walls thickly covered with very short hairs. 
In the genus Talitrus, posteriorly to this apparatus are 
placed two long ceca, one on either side of the posterior 
opening of the stomach. These ceca are not universally 
present in other genera. They are delicate prolongations 
of the walls of the stomach, and gradually narrow towards 
their free extremity. They probably supply the stomach 
with a gastric juice. Still more posteriorly, at the point 
where the stomach terminates and the alimentary canal 
commences, are situated from four to six long cxca- 
like lobes, filled with hepatic cells. These are attached 
to the inferior surface, forming the liver, and are 
carried parallel with the alimentary canal. In the 
Amphipoda, as illustrated in Gammarus, the liver con- 
sists of four sub-equal lobes; in the Jsopoda, as exempli- 
fied in Ligia, it is formed of six lobes, two of which are 
much longer than the other four, and have a slightly 
waved or tremulous-looking appearance towards the free 
extremity. From the pyloric orifice of the stomach the 
alimentary canal in all Crustacea passes, without curve or 
inflection, straight to the anal termination under the 
telson. To this we know of but a single exception, and 
that on the authority of Professor Alman, who says :— 
“In Chelura, the alimentary canal is so arranged as to 
