GENERAJL ANATOMY OF A CRAB. 201 



somewhat lower level, notice the small pyloric pouch, with 

 firm, thick, greatly folded walls. 



2. Turn the "cardiac" pouch to one side, and notice 

 the short, wide oesophagus which runs up from the mandi- 

 bles to open on its lower floor. Notice that a great part 

 of the "cardiac" pouch is anterior to the oesophaons. 

 Pass a bristle between the mandibles, through the mouth 

 and oesophagus, and notice that it projects into the cardiac 

 pouch. 



3. The liver is a very large organ, which not only runs 

 out along the edge of the carapace, as shown at i in Fif. 

 100, but also runs under the stomach and the heart, and 

 fills the greater part of the body cavity. Notice that it is 

 divided up into lo])ules, and carefully examining one of 

 these lobules, notice that it consists of great numbers 

 of small hepatic tubules, which are so loosely bound to- 

 gether that they readily separate fi-om each other, or " fray 

 out." Notice that the tubules converge on each side of 

 the body to form an hepatic duct, which opens into the 

 pyloric chamber of the stomach. 



4. The ''pylonc'' coeca. These are a pair of long, 

 slender, white, convoluted tubes, which are twined be- 

 tween the ovaries, the liver, and the mandibular muscles, 

 on each side of the pyloric pouch, into which they open. 



5. The intestine (Figs. 103 and 104 /) is a long, sti-aight, 

 transparent, dark-colored tube, which rans along the mid- 

 dle line of the body below the heart and posterior branches 

 of the ovary, from the pyloric pouch to the anus, which is 

 on the ventral or upper surfjice of the tip of the abdomen. 



6. The intestinal coecum is a long coiled tube (Figs. 

 100, 103, and 104, q) which opens into the intestine in 

 the second abdominal somite. It consists of two parts : a 

 convoluted portion which forms a compact ball (Fig. 



