164 



PEOF. ST. GEORGE MIVAET ON 



A. Living zoospores 



" " oum inerme. 



Fig. 12. 



the zoospore to which the flagellum is attached Fig. 11, 



its body appears to be homogeneous for about 

 one third of its whole size. The hinder part 

 of the zoospore contains a whetstone-like cr^'-s- 

 tal, so placed as to extend along the axis of the 

 body, and it is surrounded by fatty granules. 

 In the fresh state no nucleus is to be detected ; 

 but the application of osmic acid makes mani- 

 fest a nucleus filling nearly the whole of the 

 homogeneous part of the zoospore. 



Unripe capsules contain irregular zoospores of Collozi 



which are irregular and angular in shape, and are ^ ^^"^®„^'^3f ■„ ■ ?°*^' 

 . ° , " "^ ' spores of Collosphcsra 



not yet entirely disconnected from each other, HuxJeyi. (After Hert 

 but which nevertheless have often a flagellum, ^'^'^ 

 Zoospores without Crystals. 



The developmental processes which take place without the for- 

 mation of crystals seem to be more complex and difficult to un- 

 derstand than the others. 



The first stage is quite like that 

 of the mode of development with crys- 

 tals. In the second stage the nuclei 

 become much divided. 



This process goes on while certain 

 of the divided parts cohere together 

 to form masses of different sizes,which 

 together fill the capsule, and consist 

 of nuclei with or without a sarcodic 

 investment. 



The oil-globules meanwhile may ap- 

 pear in the form of one large central 

 one* or may be numerous and equal- 

 sized, or there may be one large cen- 

 tral one with smaller ones around it. 



The heaps of aggregated nuclei then 

 grew polyhedric, and ultimately each 

 capsule comes to be filled with aggre- 

 gated masses of larger or of smaller 

 size, and in a more subdivided or a less subdivided condition. As 

 regards the more finely subdivided masses, each such mass consists 



* In Oienkowsti's figure no. 21 we have one oil-globule in the middle of each 

 aggregation, as also apparently in Haeckel's pi. xxxv. fig. 12, and we have a 

 single central one depicted in his plate xxxv. fig, 11. 



Capsule of Collozoum inerme 

 without cry.stals, with oil-glo- 

 bules of different sizes. The 

 nuclei are seen dividing, one 

 (at 11) into five parts at once, 

 y, yellow cells. (After Hertwig.) 



