PATELLA. 217 



is twisted round through the same angular distance 

 (fig. 22). 



(c) Obliquely transverse folds running across the wall 

 space from the single divided fold (b) almost to the pair 

 of folds (a) (fig. 18). 



Where the crop narrows down posteriorly the transverse 

 folds of its walls cease, but the longitudinal ones are 

 continued until the gut begins to run forward on the 

 right side. At a certain level all folding ceases, and 

 this point should probably be taken as the termination of 

 the crop. 



The Stomach (figs. 4, 6, 10, 19, 20).— Beyond the crop, 

 the now thin-walled gut runs forward for a short 

 distance and then bends over on itself and becomes a 

 large coil which encircles the dorsal surface of the 

 digestive gland. The whole of this region may be called 

 stomach. At the point where the stomach bends over on 

 itself the duct of the digestive gland opens into it on the 

 left (fig. 19). This opening is fairly conspicuous, and 

 the wall of the duct has a groove with thickened pro- 

 jecting sides (figs. 19 and 20). This groove is continued 

 along the inner wall of the stomach throughout the whole 

 of the superficial coil, and becomes indistinct where the 

 stomach narrows down and passes into the intestine at 

 the right side of the visceral mass. At the point of 

 bending, near the opening of the duct, there is an inward 

 nap-like projection of the posterior wall (fig. 19). 



Intestine. — Numerous coils of intestine (figs. 4, 6, 10, 

 21) form the remainder of the gut. 



(a) A coil following the stomach, running back along 

 the right side, then round just ventral to the crop, 

 returning finally to the right anterior corner of the 

 visceral mass. This coil has a relatively wide cavity (fig. 

 10, Int. 1). 



