338 RESEARCH IN PROTOZOOLOGY 



in the microspore. Cepede (1911) and Strickland (1913) made 

 similar observations in Gurlcya richardi and Thelohania fibrata 

 respectively. Guyenot and Ponse (1926) expressed their opinion 

 that the macrospore and microspore may not react to chemical 

 reagents in the same manner. On the other hand, Schuberg (1910) 

 observed that the two types of spore of Plistophora longifilis w^ere 

 similar in structure. The writer agreed with this view. 



c) How are the two types of the spore produced? Hesse noted 

 in Thelohania jamis, octosporous and tetrasporous sporonts gave 

 rise to the microspores and macrospores respectively. The writer 

 saw a similar condition in Thelohania opacita (Kudo, 1922). 

 Guyenot and Ponse (1926) noted in Plistophora hufonis that 

 there were two types of schizogony which resulted in producing 

 some sporonts in which four, eight or about sixteen macrospores 

 become developed and others in which thirty-two to about sixty- 

 four microspores become formed. Thus it seems that the so-called 

 dimorphism of the spores of polysporoblastic species is due to the 

 number of sporoblasts which develop in the sporont. 



d) What is the significance of the dimorphism? Vaney and 

 Conte (1901) supposed that the macrospore serves for propagation 

 of the parasite within the host body, while the microspore for in- 

 fection of new host individuals. Guyenot and Naville (1922a) 

 who noted an ambiguous dimorphism (macrospore 4// long and 

 microspore 3/^ long) in Plistophora (Glugea) danilewskyi, were 

 inclined to suppose that an anisogamy precedes the formation of 

 macrospores, while the microspores are produced "asexually." 

 In P. bufonis, Guyenot and Ponse (1926) saw three chromatin 

 granules ("haploid") in the sporont which is destined to pro- 

 duce the microspores, without however succeeding in finding the 

 number of chromatin granules in the nuclear division of macro- 

 sporoblastic sporonts. 



The writer held, and still holds, that in at least Theloliania 

 opacita the large and small spores are simply due to development 

 of four and eight spores In a sporont, and does not find any signifi- 

 cance such as is briefly considered here. 



6) Artificial cultivation. Attempts to cultivate microsporidia 

 have so far failed. Even the actual emergence of the sporo- 

 plasm has been observed in few cases. Investigation with 

 respect to artificial cultivation of the microsporidian is highly 

 desirable. 



