90 PROTOZOA 



papers in his Beitr. Nied. Org. The Chytridieae, usually ascribed 

 to Fungi, are so closely allied to this group that Zopf proposes 

 to include at least the Synchytrieae herein. 



This group is very closely allied to Sporozoa ; for the absence 

 of cytogamy, and of sickle-germs, 1 and of the complex spores and 

 cysts of the Neosporidia, are the only absolute distinctions. 



6. Mycetozoa (Myxomycetes, Myxogastres) 



Sarcodina moving and feeding by pseudopodia, with no skeleton, 

 aggregating more or less completely into complex "fructifications " 

 before forming 1- nucleate resting spores; these may in the first 

 instance liberate flagellate zoospores, which afterwards become 

 amoeboid, or may be amoeboid from the first ; zoospores capable of 



forming hypnocysts from which the contents escape in the original 



form. 



1. Aggregation taking place without plastogamy, zoospores amoeboid, with 



a clear ectosarc ..... Acrasieae. 



Copromyxa Zopf; Dictyostelium Brefeld. 



2. Aggregation remaining lax, with merely thread-like connexions, except 



when encystment is to take place ; cytoplasm finely granular throughout ; 

 complete fusion of the cytoplasm doubtful . . Filoplasmodieae. 



Labyrinthula Cienk. ; Chlamydomyxa Archer ; Leydenia (?) Schaud. 



3. Plasmodium formation complete, eventuating in the formation of a com- 



plex fructification often traversed by elastic, hygroscopic threads, which 

 by their contraction scatter the spores ; zoospores usually flagellate 

 at first ...... Myxomycetes. 



Fuligo Hall. ; Ghondrioderma Rostaf. ; Didymium Schrad. (Fig. 30). 



I. The Acrasieae are a small group of saprophytes, often in the 

 most literal sense, though in some cases it has been proved that 

 the actual food is the bacteria of putrefaction. In them, since 

 no cell -division takes place in the fructification, it is certain 

 that the multiplication of the species must be due to the fissions 

 of the amoeboid zoospores, which often have the habit of Amoeba 

 Umax (Fig. 1, p. 5). 



II. Filoplasmodieae. Chlamydomyxa 2 is a not uncommon 

 inhabitant of the cells of bog-mosses and bog-pools, and its 

 nutrition may be holophytic, as it contains chromoplasts ; but it 



1 Even the Acystosporidiae have sickle-germs (blasts) in the insect host. 



2 See Zopf, Beitr. Nied. Org. ii. 1892, p. 36, iv. 1894, p. 60, for the doubtful 

 genus Chlamydomyxa; Hieronymus, abstracted by Jenkinson, in Quart. J. Mier. 

 Sci. xiii. 1899 ; Penard, Arch. Protist. iv. 1904, p. 296. 



