Hardwicke's science-gossip : an illustrated medium of interchange and gossip for students and lovers of nature . ofexposing the food for an extended period to theaction of the gastric fluids. Erom the stomach the food passes into the ali-mentary canal. This, at first narrow, expands at ashort distance from the stomach, again contracts,and again expands at its extremity. The intestinal canal is enveloped on each side bya dark granular mass of fatty tissue called the fat-body. This substance exists in a greater or lessdegree in all the Arachnida pulmonaria; and when we 130 HARDWICKES SCIENCE-GOS
Hardwicke's science-gossip : an illustrated medium of interchange and gossip for students and lovers of nature . ofexposing the food for an extended period to theaction of the gastric fluids. Erom the stomach the food passes into the ali-mentary canal. This, at first narrow, expands at ashort distance from the stomach, again contracts,and again expands at its extremity. The intestinal canal is enveloped on each side bya dark granular mass of fatty tissue called the fat-body. This substance exists in a greater or lessdegree in all the Arachnida pulmonaria; and when we 130 HARDWICKES SCIENCE-GOSSIP. [June 1, 1S6S. consider the precarious nature of their food, and thelong fasts which they must consequently endure, weat once see the absolute necessity of some suchinternal provision for their support. That spidersare capable of existing for a long time withoutfood has been amply proved. As an instance ofthe kind, I may cite the case mentioned by , in his admirable work on British Spiders,of a female Theridion quadripunctatum whichlived for eighteen months in a closed bottle with-out Fig. 122. Tfigenaria civilits magnified, showing alimentarycanal, &c, the fat-body being removed from one , Stomach, with caec»; A, Intestinal canal; c, Biliaryorgan; d, Renal organ; e, Fat-body. Embedded in the fat-body on each side of theintestinal canal is a series of dark glandular masseswhich communicate by means of short tubes withthe canal at the point of its first dilitation. Thisis the biliary-organ. Its existence was formerlydenied, it having been frequently overlooked in thegeneral mass of the fat-body. Also enveloped by the fatty substance, and rami-fying amongst it, are two fine tubes ; these unite ina small sac which communicates by a short tubulewith the intestine near its anal dilatation. Theproper function of this apparatus is somewbatdoubtful, but it is considered probable, and I thinkwith reason, that it is a renal organ. At the base of the abdomen
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