SARCOSPORIDIA 



531 



while, farther in, chambers with the fully-developed pansporoblasts 

 are found, and, still farther in, is the centre of the parasite, filled 

 by a granular substance formed from broken-doWn and dead spores 

 which have been too long in existence. 



As to the spores, a curious point to be noted is that some observers 

 only describe gymnospores, while others only describe chlamydo- 

 spores. Minchin suggests that this is because parasites in different 

 stages of their life-history have been examined, and he looks upon 

 the gymnospores as merozoites and the chlamydospores as spores, 

 and these views are strongly supported by Korte's description of a 

 form in Macacus rhesus. 



The merozoites are crescent-shaped, naked spores, from i to 21 

 in length, according to the species, consisting of a finely granular 



Fig. 188. — Sarcocystis tenellcB bubali Fig. 189. — Sarcocystis Spores 

 IN Meat. found in the Blood of Bos indi- 



CUS BY CaSTELLANI AND StURGESS. 



thought to be the means by which the parasite spreads itself in 

 its host, especially as they are motile by gliding, corkscrew, or 

 amoeboid movements. 



The spores are from 3 to 14 long in Sarcocystis tenella, with one 

 extremity rounded and the other pointed. They are curved, and 

 surrounded by a thin membrane. The pointed third of the spore is 

 spirally striated, due to fine folds in the outer capsule, while the 

 blunt third contains a nucleus. It is obvious that this resembles 

 the spore of a myxosporidian, and, in fact, Van Eecke says that 

 one, two, or even three filaments issue from a spore. The spores can 

 be seen in the peripheral blood at times. 



It is thought that these spores spread the infection to another 

 host, but in what manner is not clear. Perrin has recently sug- 



