CONTEIDUTIOXS TO THE CYTOLOGY OF THE BACTEEIA. 405 



tumescens. In a later paper (Meyer, 1899) he extended 

 these observations to a number of other Bacteria. He 

 •employed various methods— chiefly fixation with forinol and 

 stainiug with fuchsiii. The granules, Avhich are nuclei, may 

 be from one to six in number iu each cell. lu 1904 he gave 

 a detailed account of the chemical and staining reactions of 

 " volutin " granules in Bacteria and other organisms. More 

 recently (Mej^ei*, 1908) he afKrms that his "nuclei" are not 

 volutin, but condemns the nuclear sti'uctnres described by the 

 majority of other workers. 



Wagner (1898) discovered a nucleus in the form of a 

 granule, dividing with a dumbbell figure — one in every cell 

 — in B. coli and B. typhosus. His preparations were 

 *' dried in the usual way" and stained by a very elaborate 

 method. 



"Chromatin" bodies were found in various forms of 

 ]3acteria by Ziemann (1898). He made dry films, fixed iu 

 the flame or in alcohol, and stained by Romanowski's 

 metliod. 



Macallum (1899) investigated three species of Beggiatoa, 

 after various methods of treatment. He finds no such 

 differentiation as described by Biitschli. Compounds of 

 masked iron and organic phosphorus are uniformly diffused 

 through all the protoplasm, and these compounds also occur 

 in certain granules which stain with htematoxylin. "There 

 is no specialised chromatin-holdii:g structure in the shape of 

 ■a nucleus of any kind." 



Rowland (1899) records the results of stainiug various 

 Bacteria — chiefly with roseine, without fixation. Deeply 

 stainable granules were found, though no very definite inter- 

 pretation was given to them. He appears to think that they 

 may be partly nuclear and partly excretory. 



Under the name Bacterium gammari, a large nucleate 

 organism — inhabiting the body cavity and hasmolymph of 

 O am mar us zschokkei (from Garschiua Lake, Switzerland) 

 — was described by Vejdovsky (1900). The oj-ganisms Avere 

 treated by various cytological methods. Each cell has a 



