200 HENRY LESLIE OSBORN 



The globular body of the cell is eiith-e on its inner side; that is, 

 there are no processes given off from it. The bodies of these 

 cells contain a large clear nucleus. There is no cell wall. The 

 cells stain readily with iron-haematoxylin. Their bodies which 

 lie on nearly the same level constitute a faint zone parallel with 

 the surface of the body. 



The position and, to a certain extent the structure of these 

 cells, remind one of the cells found by Blochmann ('96) in tre- 

 matodes and cestodes in a similar situation. I have not had 

 access to this paper of Blochmann, but several writers have re- 

 produced his figures, among them Pratt ('09) who, in his recent 

 paper on the cuticula, copies a figure from Blochmann of the wall 

 of th'e cestode Ligula and designates ' sub-cuticular cells' certain 

 cells which show great resemblance to those of Clinostomum to 

 which I have just referred. There are some differences between 

 the cells in Pratt's figure and those in fig. 7 of this article. In 

 Ligula the cell body is sharply angulated on its inner side and pro- 

 duced into fine threads, which are lost in the deeper parenchyma. 

 Externally also the cells soon taper to a very fine thread. In 

 spite of these differences however it seems quite reasonable to 

 regard these cells in their relations to the body structure as a ' 

 whole as identical with the sub-cuticular cells of Clinostomum 

 just described. Benham ('01) gives a diagram of the structure 

 of the body wall of Ligula which has cells more like those seen in 

 Clinostomum. It is held by some writers that these are epithe- 

 hal cells which have sunken from a position originally on the sur- 

 face. The Clinostomum sections do not supply any evidence in 

 support of the view that these cells are epithelial in origin. 



THE PARENCHYMA 



The interspaces among the organs within the body are per- 

 meated by the usual network of branching fibers emanating from 

 large nucleated cells. In places where the parenchyma comes in 

 contact with the surface of the walls of various organs such as 

 the oesophagus (fig. 8) and the uterus, but not of all (not of the 

 intestine, for example) its fibers become much more numerous 



