Cytology and Movements of the CyanophycecB. 333 



Fig. 22. Portion of Fig. 21. more highly magnified, showing the 

 chromatin balls. 



Fig. 23. Same as Fig. 22, but showing the chromatin balls dividing. 



Fig. 24. Chromatin vesicles crushed out of a cell of Oscillaria. 



Fig. 25. Portion of filament of O. Froehlichii treated with iodine and 

 sulphuric acid. The protoplasmic threads are shown, which con- 

 nected the end cells with the neighboring protoplasts. 



Fig. 26. Portion of filament of Oscillaria plasmolized with 95 per cent, 

 alcohol. Shows each point of the contracted protoplast directed 

 toward an opening in the cell wall through which it passed. 



Fig. 27. An isolated cell of Oscillaria treated with iodine and sulphuric 

 acid and viewed from the "end." Shows the openings in the cell 

 wall and the finger-like processes of the protoplast which passed 

 through them. 



Fig. 28. Isolated cell of Oscillaria viewed from the end. The central 

 body here has assumed a deeply staining granular, irregular condi- 

 tion, which probably precedes the formation of the heavy chromo- 

 somes. 



Fig. 29. Copy of Fig. 42 in Fischer's "Untersuchungen ueber den Bau 

 der Cyanophyceen u. Bakterien." This figure shows what Fischer 

 considered to be radiating membranes from the ground mass of the 

 central body. Compare with Figs. 38 and 40. 



Fig. 30. Cross-section of Oscillaria trichome, which has been cultivated 

 in a full nutrient solution. The chromatin vesicles are very large 

 and chromatic. The radiating lines from the ground mass of the 

 central body are also accentuated. 



Fig. 31. Cross-section of Oscillaria trichome, which shows the chroma- 

 tin vesicles of the central body, and the kinoplasmic threads radiat- 

 ing from it to the cilia. 

 Fig. 32. Copy of Fig. 44, from Fischer's "Untersuchungen ueber den 

 Bau der Cyanophyceen u. Bakterien." This figure shows in cross- 

 section what Fig. 29 has in side view. These radiating membranes 

 are evidently the radiating kinoplasmic threads which pass from the 

 central body to the cilia. 

 Figs. 33-36. Successive stages in the formation of the long hair-like 



organs on the end cells of Oscillaria. 

 Fig- 37- Portion of trichome of Oscillaria grown in full nutrient solu- 

 tion. The chromatin vesicles are greatly enlarged. 

 Fig. 38. Portion of filament of Oscillaria showing the radiating lines 



from the central body or nucleus, and the cilia along the sides. 

 Fig. 39. Same as Fig. 38. Note the characteristic irregular arrange- 

 ment of numbers of cilia on each cell. 



