COXTRIBUTIOXS To THE CYTOLOGY OF THE BACTEPJA. 409 



Dietrich (1904), after reviewing tlie literature on the subject, 

 says : " VVir AvoUen nur iioch als Hauptergebnis betonen, 

 dass alia Versuche, Kerne in Bakterien zu findeii, als 

 gescheitert zu betrachten sind." 



Preisz (1904) gives an elaborate account of the structure 

 of the anthrax Bacillus. He studied the organisms after 

 mixing them with alcoholic fuchsin, formol-fuchsin, or methy- 

 lene blue. He maintains that the nuclei described by 

 Schottelius, Nakanishi, etc., are really more deeply coloured 

 portions of the cytoplasm. The real nuclei are in the form 

 of minute spherical corpuscles, one or more in each cell. 

 They undergo division. They are distinct from the meta- 

 chromatic granules of Babes and Ernst, and from the acid- 

 fast granules of Bunge. A nucleus enters into each spore. 

 He finds similar nuclei in B. cohaerens, B. tetani, and B. 

 asterosporus. His conclusions are therefore essentially 

 the same as those of Meyer. (Cf. here also Georgevitcb 

 [1910].) 



Rayman and Kruis (1904) describe typical nuclei — simiUir 

 to those found by Vejdovsky and Mencl — in a variety of 

 Bacteria (B. mycoides, B. tumescens, etc.). They are 

 found in young cells only. The method of treatment is 

 peculiar — fixation by desiccation (in a desiccator) and staining 

 with iron-h»matoxylin and purpurin. Excellent photo-micro- 

 graphs are given. The conclusions of these investigators are 

 challenged by Guilliermond (1908). 



Swellengrebel (1906) records the results of a minute cyto- 

 logical and micro-chemical investigation of Bacillus maxi- 

 mus buc calls. He finds a nucleus present in the form of 

 a more or less complete spiral or zig-zag filament. In the 

 following year (Swellengrebel, 1907), he describes two large 

 spherical nuclei in Bacterium bin ucleatum — an organism 

 from the human month. He also describes spiral or zig--zag 

 nuclear filaments or rodlets in Spirillum giganteum 

 (Swellengrebel, 1907a), and subsequently (1909a) in certain, 

 filamentous Bacteria (Sphserotilus, Thiothrix). His 

 results have been questioned by HoUing (1907), Zettnow 



