STUDIES OK THE ECTOPARASlTIC TEEMATODES OF JAPAN. XOl 



efferent ducts can not be observed when the cells are not in an 

 active state. I believe Lorenz'^ had the prostate glands before him 

 when he speaks of cells around the uterus, which had a granular 

 protoplasm. 



In Diclidophora the prostate glands are more scattered than in 

 the genera hitherto tre-ated of, and are especially abundant around 

 the terminal portion of the vas deferens. In this genus also, the 

 cells are wholly destitute of external membrane, the protoplasm is 

 finely granular, and the nuclei, which are more or less vesicular in ap- 

 pearance, vary much in size. The larger ones are more or less oval, 

 and contain a large nucleolus enclosing a vacuole, and a few smaller 

 nucleoli. After secretion the cells seem to shrink to a very small size, 

 and in these shrunken cells the efferent ducts are very distinct (PI. 

 XI, fig. 4). The interior of the vas deferens is filled with numerous 

 coarse granules, evidently the secretion of the prostate glands. This 

 secretion seems to form at first a single drop for each cell and then to 

 break up into numerous, smaller granules (PI. XI, fig. 4). In On- 

 chocotijle the prostate glands are present not only around the vas 

 deferens, but also on the more ventral side of the body (PI. XVI, 

 fig. 8). The cells are very similar to those of Hexacotyle. 



In Epibdella the prostate gland is an egg-shaped, or elongated 

 cylindrical, hollow body, lying just behind the penis and communi- 

 cating with its cavity either directly or by means of a short canal 

 (PI. XXVI, figs. 1, 3, 4, & 6). In Epib. ovata (fig. 6) the wall is 

 composed of a coarsely granular, well staining substance, and has a 

 distinct basement membrane which separates it from the mesenchyma. 

 In a specimen of Epib. Isliikawae which I examined, the cavity 

 contained a well staining, homogeneous coagulum which looked very 



1). Lorenz — Ueber die Orgmiaation der Gattungen Axine u. Microcotyle. Wiener Arbei- 

 ten, Bd. 1, 1877, p. 8. 



