526 The Development of a Parasite of Earth-worms. 



normal saline solution is placed on a cover-glass, which is then inverted and 

 allowed to fall flat on to the set jelly film. The spermatozoa, the nuclei of 

 the epithelial cells and of the seminal cells all stain deeply. Within the 

 epithelial cells the parasites also stain in sharp contrast with the surrounding 

 cytoplasm, so that their morphology can be readily determined. The first 

 stage of the parasite within the cell consists of a blue dot or granule situated 

 in what looks like a vacuole which colours only faintly (Plate 14, fig. 1). In 

 the next stage observed, the dot has apparently divided, for the .vacuole or 

 sac now contains several blue granules (fig. 2). The dots then elongate into 

 rods (fig. 3), and each rod becomes lengthened and splits longitudinally (fig. 4), 

 until the parasite appears like a bunch of painted sticks — a sheaf embedded 

 within the cytoplasm of the epithelial cell, its host. This process of splitting 

 continues and at length there is a series of spiral coils wound up within the 

 sac, which is still enveloped by the protoplasm of the epithelial cell 

 (figs. 6 and 7). 



In some specimens observed by the jelly method, the parasite is separated 

 from its host-cell, and is found stained and lying free as in fig. 5. The final 

 stage is that of a free spirocheete (fig. 8). This is the fully developed parasite, 

 having a long slender body, pointed at one end and blunt at the other. 

 It is nearly always found coiled up, but occasionally it is almost straight. 

 Its protoplasm is homogeneous, and contains at irregular intervals in its 

 length small chromatin masses, varying in number from five to twelve, 

 which are characteristic of spirochetes. These spirochetes have not only 

 been seen free, but also swimming actively in the seminal fluid when the 

 latter has been examined by dark ground illumination. They are readily 

 differentiated from spermatozoa by their length, granulation, and peculiar 

 movements, nor can there be any confusion between this parasite and the 

 well-known Monocystis Lumbrici or the spermatophores. So far as I can 

 ascertain, its existence has not been recorded before. It is interesting to 

 note, however, that intracellular phases of spirochetes have been described 

 in other animals by A. Balfour, H. B. Fantham, E. Hindle, Sir William 

 Leishman, and others. Its resemblance to the parasite of the guinea-pig is 

 very remarkable ; the earth-worm parasite is larger however, develops in the 

 fixed epithelial cells of the vesiculae seminales, and has not been seen in the 

 blood of its host nor in the coelomic fluid, but it passes through corresponding 

 phases. The parasite is present in about one earth-worm out of five. 



Summary. 



A description of " bodies " found within some of the epithelial cells of the 

 vesicular seminales of the earth-worm. They closely resemble "Kurloff's bodies" 



