210 



Chlorococcineae 



Sub-family CHLOROCHYTRIE^E. As here constituted this group includes 

 the genus Chlorococcum and those Algae which have been placed for some 

 time past in the ' Endosphseraces;.' All of them are characterized by 

 the rounded or ellipsoidal nature of their cells or ccenocytes, which are for the 

 most part endophytic. 



Fig. 137. A, Chlorochytrium Lcmnss, Cohn ; , part of leaf of Lcmna trisulca, with three 

 Chloroehytrium-cella ; a young cell showing pyrenoids, a fully-developed one, and an empty 

 one; b, gamete; c, zygozoospore; a, x 300 ; b and c, x 720. B, Chlorochytrium bienne 

 (Klebs) G. S. West; a, a large winter resting-cell which has divided into many cells; b, one 

 of the cells; c, formation of gametes in this cell; d, gamete ; c, zygozoospore ; a d, x 800 ; 

 e, x 720. C,PhyUobhiin dimorphum Klebs ; a, empty resting-cell ; b, microgamete ; c, mega- 

 gamete ; d, fusion of anisogametes ; e, zygozoospore ; /, germination of zygozoospore ; 

 g, young Phyllobium-ce\l ; a, x72; b g, x 720. D, Chlorochytrium Cohnii (Wright) G. S. 

 West ; a, vegetative cell ; b, gamete ? ; c and d, development of motile cells ; all x 450. 

 E, Chlorochytrium paradoxum (Klebs) G. S. West ; a, resting-cell which has formed zoo- 

 gonidia (b), x 360 ; c e, germination-stages, x 720. (D, after Lagerheim ; remainder after 

 Klebs, from Wille.) 



The best known genus is Chlorochytrium (fig. 137 A and B ; fig. 138-4), the 

 cells of which are ellipsoid, ovoid, or somewhat irregular, occurring either in 

 the intercellular spaces or wedged in between the peripheral cells of aquatic 

 macrophytes (Ceratophyllum demersum, Elodea canadensis, species of Lemna) 

 and plants which grow in damp situations (Mentha aquatica, Rumex obtusi- 

 folius, Lychnis Flos-cuculi, etc.). Some species are marine, occurring in the 



