PL. III. 



Fig. 1. Chilodon (?) sp. Fresh state, probably dead. From a pond on a comparatively 

 clean ice-floe. July 24, 1894. Magnified about 760 diameters (Zeiss obj. F, oc. 2, 

 cam. luc). 



— 2. Chilodon sp. Fresh stale, probably dead. From another pond on the same 



ice-floe as above. July 24, 1894. Magnified about 760 diameters. (Zeiss obj. F, 

 oc. 2; cam. Inc.). 



— 3. Chilodon sp. Living. Conjugation of two individuals probably of the same species 



as above. From the same place as above. July 24, 1894. They were observed 

 in this situation, unaltered for a long while. The vacuoles were the whole time 

 pulsating. They were moving rapidly, being dragged along by the one individual. 

 At last they died (Zeiss F, 2, freehand). 



— 4. Chilodon sp. Killed with Chromo-Aceto-Osmic-Acid. From same place as above. 



July 24, 1894. v Vacuoles. Magnified 700 diameters. (Zeiss obj. F, oc. 2; cam. 

 luc). 



— 5. Chilodon sp. Fresh state, probably dead. From the same ice-floe as above. 



July 24, 1894. Individual of the same species as above seen from the end. The 

 pointed (anterior) end is near the margin at a. and would have become visible, 

 outside the margin, by a slight turn of the animal. The double series of cilia 

 wind round the body and meet at its end, at c. Magnified about 760 diameters. 

 (Zeiss F, 2; cam. Inc.). 



— 6. Chilodon sp. Fresh state, just dead. From the same sample as Fig. 3. Magni- 



fied about 760 diameters. (Zeiss obj. F, oc. 2; cam. luc). 



— 7. Chilodon sp. Killed with Chromo-Aceto-Osmic-Acid, stained with Borax-Carmine. 



From pond on the ice. July 27, 1894. Same species as Figs. 1—6, the specimen 

 is seen from the anterior pointed end which is at a. v Vacuoles, a third vacuole 

 is seen on the other side. The oral opening was very distinct. Magnified 1000 

 diameters. (Zeiss F, 3; cam. luc). 



— 8. Stylonychia, (?) sp. This is probably a cyst of the same form as PI. IV, Fig. 1. 



It was quite motionless. Thick stiff hairs at both ends. 

 Magnified 460 diameters (Zeiss obj. CC, oc. 5; cam. luc). 



— 9. Chilodon (?) sp Living, in active motion. From a pond on the ice, seen with 



specimens of the dark and the transparent forms of Lacrymaria. July 28, 1894. 

 Magnified about 460 diameters (Zeiss obj. CC, oc. 5, freehand sketch). 



— 10. Living, in active motion. From a pond on the ice. July 28, 1894. Small animals 



of this kind were often seen amongst the algse from the ponds on the ice. It is 

 possibly the same species as Fig. 12; but as far as could be seen the cilia were 

 chiefly situated on the one side only. They had a twitching and one-sided motion. 

 Half an hour later all movement had ceased, and two colourless water-clear refrac- 

 tive drops were secreted from each side (Fig. 11). During this process the animal 

 was reduced to a small globule (Fig. 11); its protoplasm became less transparent 

 and the grains closer together. 



Magnified perhaps about 460 diameters (Zeiss obj. CC, oc. 5; freehand sketch). 



— 11. Same individual as Fig. 10. (Zeiss CC, 5; freehand sketch). 



— 12. Living, in active motion. From a pond on the ice together with specimens of 



Chilodon. July 28, 1894. Animals of this small kind were often observed. They 

 v'were always as small as this individual. They seemed to be round in transverse 

 section and covered with cilia all over. Magnified about 460 diameters. (Zeiss 

 obj. CC, oc. 5; freehand sketch. 



