816 SUMMARY OF CURRENT RESEARCHES RELATING TO 



dium was observed, resulting iu a multinucleated mass. At a cer- 

 tain stage the amoeba) form zoocysts, sometimes 250 //, in length, 

 and 63 /z in thickness, enclosed in a smooth, colourless, cellulosc-liko 

 membrane. A peripheral layer rich in paramylum granules, a more 

 or less gigantic vacuole, containing undigested food, and numerous 

 nuclei were readily distinguishable. The peripheral protoplasm 

 eventually divides into two or more portions, forming young amoeba), 

 which escapo through special holes in the wall of the cyst. The 

 Lcptoplirys is undoubtedly able by its secretions to dissolve the 

 carbohydrate and albuminous material of tho algoid cells on which it 

 is parasitic. Tho former results in paramylum ; the latter nourishes 

 protoplasm and nuclei. 



II. Vampyrella spirogyrse Cienk. In this form, with its three 

 phases — amoeboid, zoocyst, and sporocyst, the protoplasm was seen to bo 

 differentiated only in the amoeboid stage, but the structure was much 

 obscured by the ingested food-material. An amoeboid body (nucleus ?) 

 and contractile vacuoles were, however, demonstrable. 



III. Vampyrella variabilis Klein. Amoeboid corpuscles (nuclei ?) 

 and contractile vacuoles were demonstrated both in the amoeboid and in 

 the encysted phase of this parasite. Ha3matoxylin in alum solution 

 was used for staining the living organism. 



IV. Vampyrella pendula Cienk. Nuclei were observed not only 

 in amoebae and zoocysts, but also in young sporocysts. Besides 

 these, one or more vacuoles occurred. 



V. Protomonas amyli Cienk. The amoeboid forms were put into a 

 drop of distilled water, the margins of the cover-glass were smeared 

 with " Provencerol " to keep out the air, with the result that all the 

 starch-grains were expelled. In the transparent amoebae the nuclei 

 were then demonstrable. 



In the second part of his memoir Zopf describes a number of new 

 Monadina. 



1. Diplopliysalis stagnalis Zopf. The cells of CJiaracese, especially 

 Nitella, were found in certain cases to contain numerous, spherical, 

 ellipsoidal, or oval bodies, enclosed in a delicate membrane, and con- 

 taining in their protoplasm orange or sepia-coloured particles, and 

 also starch-granules. There are, on an average, about 30 zoocysts in 

 a cell. Zoospores are soon formed which force their way out. These 

 spores have a cilium at each pole, and measure about 8-12 i*. They 

 exhibit a nucleus and a contractile vacuole. Division into two was 

 frequently observed, though not hitherto in any of the zoospore-form- 

 ing Monadina. They may leave their original cell-host and find 

 another. Finally, the ciliated spores become amoeboid forms. After 

 copious nutrition and increase in size, they pass into the encysted 

 phase (zoocysts). After a while individuals occur which form perma- 

 nent spore-fructification (sporocysts). The amoeboid form becomes 

 quiescent and enclosed in a membrane. Within this the protoplasm 

 separates itself from the food-remains, and forms a nucleated body 

 within a thin skin. In this secondary star-shaped cyst, which 

 becomes gradually yellowish brown, the protoplasm again shrinks 

 up into one or two resting-spores. 



