90 PROTOZOA 



papers in his Beitr. Med. 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/ and of the complex spores and 

 cysts of the Neosporidia, are the only absolute distinctions. 



6. Mycetozoa (Myxomycetes, Myxogastres) 



Sarcodina moving and feeding hy 2^seudopodia, with no skeleton, 

 aggregating more or less com])letely into comjjlex "fructifications " 

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

 instance literate fiagellate zoospores, which afterwards become 

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

 forming hyiJnocysts from which the contents escape in the original 

 form. 



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



a clear ectosarc ..... Acrasieae. 



Gopromyxa Zopf ; Dicfyostelium BrefelJ. 



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



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

 complete fusion of the cytoplasm doubtful . . Filgplasmgdieae. 



Lahyrinthula Cienk. ; Chlamydomyxa Archer ; Leijdenia (?) 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. 



Fidigo Hall. ; Chondrioderma Rostaf. ; Didymimn 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 oi Amoeha 

 Umax (Fig. 1, p. 5). 



II. Filoplasmodieae. — Chlamydomyxa- is a not uncommon 

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

 nutrition may l;)e holophytic, as it contains chromoplasts ; but it 



^ 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 .lenkinson, in Quart. J. Micr. 

 Sci. xiii. 1899; Penard, Arch. Protist. iv. 1904, p. 29G. 



