ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 817 



2. Diplopliysalis Nitellarum Cienk. This form, described by 

 Cienkowski as Pseudospora n&, differs from (1) mainly in the 

 character of the sporocyst. The secondary cyst membrane is not 

 stellate, but smooth or only slightly angular. In winter the contents 

 are starchy ; in summer they are yellow, or sepia-brown food-remains. 

 The ripe resting-sporo contains abundant reserve material which 

 hides the nucleus. The resting-spore gives rise to zoospores, in the 

 formation of which the nucleus is seen to break up into numerous, 

 small, uniformly distributed spheres. The 20-40 spores work their 

 way out independently. 



3. Pseudospora maligna Zopf. This form was found in the 

 protonema cells of various mosses. The zoocysts are spherical, and 

 each exhibits an execntric vacuole enclosing brown food-particles. 

 The finely granular protoplasm between vacuole and membrane 

 breaks up into small portions which form the swarm-spores. These 

 possess a single fino cilium, are extremely active, and leave the 

 original cell for another. With increased nutrition, they become 

 amoeboid. By means of their pseudopodia, they lay hold of chlorophyll 

 granules and utilize them. Finally, they pass into the encysted 

 phase. 



4. Aphelidium deformans Zopf. This form, closely allied to the 

 above, was found in a Coleocltseie associated with Nitella. Four 

 stages may be distinguished — the parasitic spore, the .amoeba, the 

 swarmspore-forming stage, and the resting-spore form. The young 

 amoeboid form grows till it fills the algoid cell as a homogeneous, 

 finely granular mass, in which the reddish-brown chlorophyll remains 

 are seen floating. No proper cyst is formed, but tho protoplasm 

 divides into numerous spores which find their way out. Restiug- 

 spores arc similarly formed, sometimes on tho same thallus. 



5. Gymnococcus Focliei. In large Diatomacea? (Pinnularia, 

 Stauroneis, &c.) spherical forms occur, surrounded by abundant, brown 

 endoehrome remains. These are zoocysts, and the protoplasm divides 

 into small amoeboid spores, which are liberated and again find their 

 way into similar cells. The endoehrome material is digested. The 

 resting-spore form was also observed, though not within a special 

 cyst. When food is deficient, the developmental history is simplified. 

 The swarm-spores become quiescent and form microcysts, which differ 

 from the zoocysts in only forming one spore, and from the resting- 

 spores, further, in the delicacy of their membrane and in the absence 

 of reserve material. 



Ser. 2.— Vol. VI. 3 H 



