i8 Maurice .Croivthcr Hall 



of which the smaller, clavate forms are in active motion and the 

 larger oval forms are stationary. Aly observations were not suf- 

 ficiently followed up to determine whether these were reserve 

 granules of the entocyte with the smaller displaying the Brown- 

 ian movement, or whether I had under observation a phase of 

 sexual multiplication such as the work of Leger (1901-4) has led 

 us to expect in gregarines. 



Cysts ripened for varying periods in water usually take on a 

 pink to red color. Occasionally tubercles appear on the surface, 

 due, as sections show% to the formation of large vacuolated areas 

 in the peripheral plasm of the cyst. I was unable to provoke 

 spontaneous dehiscence of the cysts by ripening in water, though 

 my most extended observation on this point covered cysts that 

 had ripened dry for sixty days and then b^en left in water for 

 forty-seven days. After being left dry for twenty-seven more 

 days, one cyst out of five was full of uniformly developed sporo- 

 cysts, as determined by sectioning. • Of seven cysts which had 

 ripened dry for 208 days, three showed the sporogysts on section- 

 ing, though the cyst had refused to open in water. Two other 

 cysts opened. These latter cysts showed a light yellow color 

 with a dry, shiny, slightly roughened surface and no cyst mem- 

 branes. On the addition of water, a mucilaginous cyst membrane 

 started to form, and inside of a minute had increased to a thick- 

 ness equal to the cyst diameter. Simultaneously an air-bubble 

 formed at one point on the cyst, followed by an eruption of a co- 

 herent mass of white material together with numerous other air 

 bubbles. Sections of these cysts showed no spore formation, the 

 cyst content being slightly granular and stainmg uniformly with 

 iron haematoxylin. 



In the expectation of dehiscence, I allowed the cysts to ripen 

 some time without sectioning. The earliest sporocyst formation 

 that I observed was after a period of ninety-six days, in one case 

 in a cyst ripened dry and in another in a cyst that had been in 

 water the last four days out of the ninety-six. 



In a set of fifty-two cyst sections, covering a ripening period 

 of from 80 to 208 days, eleven are achromatic at a period when 

 it certainly indicates degeneration, three have a persistent septum 



166 



