THE SPOROZOA 



plasmotomy, defined as the breaking-up of a multinucleate cell into 

 multinucleate fragments ; the plasmotomy may be either simple, 

 i.e. ordinary fission, or multiple, as in budding (Fig. 101). This 

 mode of reproduction is probably common in the free forms. 



In the second place, multiplicative reproduction may take place 

 in the youngest stages of the parasite, in the amoebula which has 



3|g"- y ;;. ; 



'b" : V 



; v-/ 

 d 



* 



FIG. 102. 



Stages of multiple amitosis in the youngest germs of Glugea lophii, Dofl. (After Doflein.) 

 (The stages given here are those of a division into four, but the products of division may exceed, 

 or fall below, this number.) 



just reached its definitive situation. The nucleus of a minute 

 individual undergoes a fragmentation into numerous daughter 

 nuclei by a process of "multiple amitosis" (Fig. 102). The proto- 

 plasm then breaks up to form numerous minute uninucleate " swarm- 

 spores," which spread the infection in the tissues of the organ 



Schizogony of Thelohania miilleri (L. Pffr.). a, "meront" with single nucleus; b and c, 

 division into two ; d and e, into four ; /, g, h, chains of meronts formed by rapid division. 

 After Stempell, x 2250 (see footnote). 



affected, or it may be in all the tissues of the host, which in this 

 way may be soon quite overrun by the parasite when once infected. 

 This method of reproduction is probably very common, if not uni- 

 versal, in the tissue and cell-infecting Myxobolidae and Glugeidae. 1 



thus giving rise to an appearance erroneously interpreted by Cohn as budding 

 (compare Fig. 101). This method of reproduction goes on actively during the 

 winter months, when no spores are produced. 



1 In Thelohania miilleri (L. Pffr.), from the muscles of Gammams pulex, Stempell 

 (Zool. Anzeiger, xxiv. p. 157) finds two kinds of trophozoites larger sporonts, which 

 produce spores, and smaller meronts, which multiply by a simple form of schizogony. 

 Each meront divides into two after direct nuclear division, but before the separation 

 of the two cells is complete, further division is commenced, so that three or four in- 

 dividuals are found connected in a group. This method of reproduction is clearly 

 intermediate in character between the two methods, plasmotomy and formation of 

 swarm-spores, described above. 



[Since this note was written, Stempell's detailed memoir has appeared [111], from 

 which Fig. 103 is reproduced.] 



