142 PROTESTS AND DISEASE 



soaked in water the cysts separate, 6, c. I have examined 

 many sclerotia of Didymium difforme but in none have I 

 found this regular segmentation. In Badhamia the segments 

 recall the multinucleate conidia of Mucor. Reviving 

 sclerotia should be watched in slide-and-cover prepara- 

 tions mounted in water. The protoplasm absorbs water to 

 form vacuoles, round which groups of oscillating granules 

 are seen; after this the segments coalesce and streaming 

 begins. 



Nuclear processes in Mycetozoa. The zoospores have a 

 contractile vacuole and a nucleus, which is placed close to 

 the insertion of the flagellum at the narrow anterior end of 

 the organism. A. Lister described the nucleus of the zoo- 

 spores of Eeticularia Lycoperdon (Journal of the Linnaean 

 Society, 1893) at rest and in division and Jahn's description 

 and illustrations, Fig. 40, a to d, confirm Lister's, and his 

 account of conjugation of swarm-cells with karyogamy at 

 the beginning of plasmodium formation has been accepted 

 in biology. 



Both de Bary and Cienkowski believed that the nuclei 

 of the swarm-cells disappeared when they coalesced to form 

 the plasmodium, Fig. 38 : la. In 1893 the fact that 

 some plasmodia have nuclei had been established by Schmitz 

 and Strasburger, as quoted by A. Lister, who wrote : "It 

 may be presumed that they are the persistent nuclei of the 

 swarm-cells and the results of their divisions." 



There is a simultaneous karyokinesis of nuclei in the 



