190 HANDBOOK OF PROTOZOOLOGY 



Family Trichiidae 



Genus Trichia Haller (Fig. 71, h-j). Capillitium abundant, 

 consisting of free elasters with spiral thickenings. 



Family Arcyriidae 



Genus Arcyria Wiggers (Fig. 71, k, L). Sporangia stalked; 

 sporangium-wall evanescent above, persistent and membranous 

 in the lower third. 



Family Margaritidae 



Genus Margarita Lister. Capillitium profuse, long, coiled 

 hair-like. 



Family Ceratiomyxidae 



Genus Ceratiomyxa Schroter (Fig. 71, m, n). 



Suborder 2 Sorophora Lister 



Pseudo-plasmodium incomplete; myxamoeba a Umax type 



Family 1 Guttuliniidae 

 Pseudo-plasmodium complete; myxamoeba with short pointed pseudopodia 



Family 2 Dictyosteliidae 



Appendix 



The Proteomyxa and the Mycetozoa as outlined above, are 

 not distinctly defined groups. In reality, there are a number of 

 forms which stand on the border line between them. 



Phytomyxinae Schroter 



These organisms which possess a large multinucleate amoe- 

 boid body, are parasitic in various plants and also in a few 

 animals. They do not form any sporangium and their methods 

 of spore-formation are simple. 



Genus Plasmodiophora Woronin. Parasitic in the roots of 

 cabbages and other Cruciferae. The organism produces knotty 

 enlargements, sometimes known as "root-hernia," or "fingers 

 and toes" (Fig. 72, a). The small spore {b) gives rise to a 

 myxoflagellate {c-e) which penetrates into the host cell. The 

 organism grows in size and the nucleus divides (g). Several 

 myxamoebae fuse into a Plasmodium, thus destroying the host 



