564 DESCRIPTION OF FIGURES. 



Fig. 



secondary, primordial cells, which almost fill the 

 parent-cell. Their disposition resembles that of 

 Botryocystis morum, Kg. 



39. Incomplete division of an encysted zoospore into 

 four, also encysted secondary cells, which remain 

 connected in the centre after the removal of their 

 common enveloping cell. This seems to repre- 

 sent a further development of that given in 

 figure 25. 



40. Division of an encysted cell into thirty-two minute, 

 spherical, entirely green, primordial cells, which 

 completely fill their delicate parent-cell. This 

 arrangement corresponds to the genus SpJiteras- 

 trum tesserale, Kg., or to Uvella virescens, Ehr., 

 or to Syncrypta volvox, Ehr. 



41. Zoospores from the last-described form escaped 

 from the parent-cell. One of them (a) shows 

 the formation of a membrane around it. 



42. An encysted zoospore with a spherical primordial 

 cell, the green, non-granular contents of which, 

 are retracted to one side, in a crescentic form, 

 whilst a colourless vesicle occupies the other half. 

 This modification appears to depend upon a 

 deficient supply of water. 



43. A red cell, which, by desiccation, has become 

 colourless, showing grumous contents with oil- 

 globules. 



44. A large red " still" cell, the contents of which are 

 divided into numerous (64 ?) segments. 



45. A red encysted cell. 



46. A red " still" cell, originating in the transition of 

 the cell represented in fig. 45 into the " still" 

 condition. 



47. An encysted zoospore, treated with iodine and 

 sulphuric acid. 



\* All the figures are magnified under a power of 

 500 linear. 



