Olive, Mitotir divisioii of tlie niirlei of tlie Cyauophj'ceae. lo 



portions, an outer colorod pari and an inner colorless pari, tlio 

 latter eonstituting the so called „central body". Grranular in- 

 clusions niay also frequently be seen, particularly in certain 

 species of Oscillatoria^ in whicli tliey are often arranged on botli 

 sides of and parallel to tlie cross walls. Occasionally, grannies 

 of varying size may be observed, wliicli appear to lie within 

 tlie central portion (fig. 1). 



As will be seen from tlie table on pages 2 and 3, tlie majority of 

 writers maintain tliat the bliie and green coloring matters are 

 contained botli together in niinnte granules, or plastids, wliicli 

 occur in large nnmbers scattered tlirougli tlie periplieral portion 

 of the cytoplasm. Fischer and a few others assert, on the 

 other liand, tliat the color is diffused through the dense peri- 

 plieral portion of the protoplasm. Tliis liollow cylindrical or 

 spherical part, he calls the chromatophore. The writer agrees 

 perfectly witli the Statements of Fischer in regard to the color- 

 bearing portion. 



One call see, it is triie, granules in the living cells; but all 

 the granulations whicli I have ever seen liave proved to be the 

 colorless cell inchisions. In the thinnest and niost favorably 

 stained sections, fiirthermore, both longitudinal as well as cross, 

 1 have never been able to detect in the periplieral chromato- 

 phore any granulation whatever. (See, e. g., figs. 8, 10, 16, 18, 

 32). If minnte plastids were present, they should certainly be 

 visible in the permanent preparations as well as in the living. 



The absolute failure to hnd „cyanoplastids" in thin sections 

 of any of the six genera studied does not, by the way, preclude 

 the possibility that the chloroj^hyll and phycocyanin may pos- 

 sibly be in the form of niinute giobules, which may disappear 

 on treatment witli certain reagents. But I have never been able 

 to bring myself to see such colored giobules, after many attempts 

 linder the most favorable conditions. 



In addition to the absence of plastids in stained preparations, 

 the following observations still further strengthen Fi scher' s 

 conclusions witli reference to the periplieral chromatophore. If 

 OsciUatoria FroeJdicJiia, e. g., or any other large species, be 

 placed in Chloroform water ^) for one or two days, the blue 

 coloring matter is extracted, and may then be seen dissolved in 

 the water. The Chlorophyll alone remains in the cells. A di- 

 stinct granulation may now be seen, especially in the central 

 portion, as shown in fig. 29. If liglit pressure be then applied 

 to the Cover glass, the cells of the filament may frequently be 

 broken apart and the isolated, flattened cells be turned on end. 

 Fig. 28 represcnts such a disc-shaped cell, which consists of the 

 somewhat shrunken proto2)lasm only, the wall having been torn 

 off. The bright green color will be seen in tliis end view to 



1) Made according to Hegler's dircctious by sliakin«;- uj) a small 

 qnantitj' of chloroform in water, allowiiio-. it to settle, tlieu decanting the 

 water. wliich is then used in tlie experinients. 



