STUDIES OX THE ECTOPAEASITIC T)lEMATODES OP JAPAX. 47 



radiates, in consequence, in the form of threads from around the 

 nucleus towards the cell-membi-ane. In some cases, however, there 

 ai-e no vacuoles, and the cell-body consists simply of a slightly stained, 

 granular protoplasm. In still other cases (e.r/., on the right side of the 

 prostate glands around the vas deferens in fig. 1, PI. VIII), the cell- 

 membrane is incomplete, and the boundaries of adjacent cells are 

 more or less obliterated. In the terminal portions of the body as 

 well as around the ducts of the genital organs, the endoparenchyma 

 consists of truly fibrous connective tissue interspered with small nuclei, 

 which are sometimes surrounded by a scanty mass of granular 

 protoplasm. Around the ducts of the genital organs I have often 

 observed much larger, oval or elongated nuclei surrounded also with a 

 scanty mass of granular protoplasm ; but they seem to have no special 

 function. The meshes of the connective tissue are filled in some parts 

 with slightly stained granules and- in others with a perfectly trans- 

 parent, clear fluid (PL VIII, figs. 2, 3, and 4). 



In most species of Mierocotyle, the greater part of the endo- 

 parenchyma is of a fibrous nature ,• but in some parts it consists of 

 true cells, while in others there is some tendency in it to assume the 

 character of a syncytium. Thus in Mierocotyle truncata (PL III, fig. 

 6) and M. caiiclata (PL III, fig. 9), the endoparenchj^ma consists in 

 the lateral part of the median portion of the body free fi'om the 

 vitellarium, often of polyhedral cells each usually with a distinct 

 membrane, a vacuolated cell-body, and a nucleus in the centre, from 

 which the protoplasm radiates in the form of fibres towards the 

 periphery, just as in some mesenchyma cells of Axine already de- 

 scribed. In M. caudata the vacuoles are less distinct, and the whole 

 cell is more granular and more deeply stained than in M. truneata. 

 The nucleus usually encloses a single nucleolus, but sometimes more ; 

 and the boundaries of the adjacent cells are, in many cases, more or 



