266 ]f. I.YNDHUHST DTKi:. 



were defined much more distinctly with the iron-ha3matoxylin 

 method. All tissues were embedded in paraffin, with chloro- 

 form as the intermediary fluid. 



Culturo of the cysts. — To obtain the ripe spores the 

 cysts were simply placed in the moist chamber, where, in the 

 course of seven or eight days, the spores were developed. 

 The cysts were either placed simply on a slide in a drop of 

 Neckar water or under a cover-slip provided with wax feet. 

 The cysts dehisced by simple rupture after about seven or 

 eight days. Cysts placed in normal NaCl solution in the 

 moist chamber did not develop successfully. 



StRUCTUKK f)P THE TkOPHO/OITE. 



The body is divided by septa into epi-, j)roto-, and 

 deutomerite, and is elongated in form (figs. 1-6). Some 

 individuals have a more thick-set appearance than others, 

 especially in the extreme hinder end of tlie gut, where the 

 gregarines are often crowded together. The animal measures 

 about 150^ by 45j«. At the posterior end of the deutomerite 

 there are often present indications of further subdivision of 

 the body, and occasionally as many as three complete segments 

 are seen (fig. 4). This segmentation is not confined to 

 gregarines of any peculiar build, being present in both long 

 and short forms, and it varies in the degree of development 

 of the segments. It was present in about a third of the 

 gregarines examined alive in Heidelberg, and is also very 

 distinct in the preparations of these animals made at the time. 

 The Cambridge gregarines also showed segmentation, though 

 it was distinctly less in evidence, both in the living animal 

 and in carmine preparations of it. It appears to vary greatly 

 — from the veiy faintest indication to quite definite septa. 

 It must be stated in this connection that no segmented 

 greo-arines were seen in the sections of the infected leeches, 

 though constantly found in preparations made by teasing out 

 the host-tissues. This compels one to consider the possibility 

 of injury during extraction being the cause of this segmenta- 



