L06 



Ü. TAKAKURA. 



In the epithelium are found flasc-shaped glandular cells, whose con- 

 tents stain with hannatoxylin. They are generally numerous on the 

 ventral side, while they are often entirely absent on the dorsal surface 

 and on the very tip of the head. Under the muscular layer of the 

 body-wall in the anterior region, numerous groups of glandular cells 

 are imbedded within the parenchymatous tissue. In most specimen^, 

 these groups are found in the oesophageal region, but sometimes they 

 extend far behind that part. Generally they are found in a great 

 number on the dorsal side. The ducts of these glands can not be 

 clearly observed, but it seems probable that the streaks of fine granules, 

 which are visible among the epithelial cells of the body-wall and which 

 appear to have the same nature as the secretion of the glands, indicate 

 their external ducts. At the anterior upper and lower edges of the 

 mouth, their external ducts can distinctly Ik; observed passing through the 

 basal membrane to the exterior. In a greater part of the dorsal and 

 ventral sides of the flattened lateral portion of the oesophageal region 

 these glands are much developed, but few of them are met with in the 

 anterior. Along the margins of such lateral portion, a voluminous 

 aggregation of them is situated on each side, and their external ducts 

 open at the lateral edge. These glands are abundant in the acetabulum 

 as in M. grossa, especially on its ventral side. 



The wall of the oesophagus is folded into finger-like processes, which 

 v. Kennel and others have already noticed ; when fully extended they 

 become rather slender, and those of the anterior part are protruded 

 out of the mouth opening, and are moved to and fro like tactile 

 organs. These processes, however, become short in the posterior and 

 vanish in the narrow region, which connects the oesophagus with the 

 intestine. The epithelium of the oesophagus is provided with a thin 

 tunica propria, as Bürger observed, and the sub-epithelial glands are 

 loosely imbedded on the outside of it, deeply within the body 

 parenchyma. They are most numerous a little in front of the end of • 

 the oesophagus. The intestine, which is clearly distinguished by a 

 narrow constriction from the oesophagus, makes about 10 windings, not 



