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The maxillse are corneous in their structure, and covered more or less with hair, 
they serve to masticate the food and express the juices which are then sucked 
in by the lips. In a cavity above the palate is a transparent glandular mass, 
which secretes a fluid, probably, functionally at least, the same as saliva. 
The mouth communicates by means of a short oesophagns with the stomach* 
This vessel is of a highly complicated and peculiar structure. 
It is broad and flat, semewhat circular in form, and possesses on each side five 
cylindrical ccecse, which extend up to the roots of the legs and palpi. These 
ccecse appear simply to serve the purpose of exposing the food for an extended 
period to the action of the gastric fluids. 
From the stomach the food passes into the alimentary canal. 
This, at first narrow, expands at a short distance from the stomach, again 
contracts, and again expands at its extremity. 
The intestinal canal is enveloped on each side by a dark granular mass, which 
is called the Fat-body. 
This Fat-body exists in a greater or less degree in all the Arachnida 
pulmonaria, and when we consider the precarious nature of their food, and the 
long fasts which they must frequently endure, we at once see the absolute necessity 
pf som e such provision for their support. 
That Spider3 are capable of existing for a very long time without food has been 
amply proved. As an instance of the kind, I may give the case, mentioned by 
Mr. Blackwall in his work on British Spiders, of a female Theridion quadri- 
piinctatum, which lived for eighteen months in a closed bottle without food* 
Embedded in the <c Fat-body,'* on each side of the intestinal canal is a series 
of dark granular masses, which communicates by a series of tubercles with the 
canal at its first dilatation . This is the liver, its existence was formerly denied, it 
having been frequently overlooked in the general mass of the " Fat-body.'' 
Also enveloped by the " Fat-body," and ramifying amongst its substance, are 
two fine tubes, these unite in a small sac, which communicates by a short tubercle 
with the intestine near its oval dilatation. 
The proper function of this apparatus is doubtful ; but it is considered pro- 
bable, and I think with reason, that it is a renal organ. 
At the base of the abdomen, near its extremity, there is resting on the surface of 
the ' f Fat-body " a greyish yellow mass. This, when removed from the spider and 
teased-out, is found to be composed of an immense numbar of minute tubes 
ramifying from a series of small glands. These tubes expand several times during 
their course into small sacs, and finally find their exit in a variable number of 
jointed mammulse, in the case of Tegenaria civilis, six, situated externally on the 
inferior surface of the abdomen. 
This is called the silk securing apparatus, and the external mammulse are named 
the spinnerets. 
Each mammula is studded with a number of minute orifices through which the 
secretion from the tubes passes. The number of these tubes has been variously 
estimated at from 400 to 1000 j in some specimens of Tegenaria civilis I examined, 
I found the number was about 720. It has been generally stated, that the whole 
of the six mammulse are engaged in the formation of a single thread of spider's 
silk ; this, however, I am very much disposed to doubt, and from what I have 
seen I am inclined to believe that only one or two of the mammulse are in action 
