CONTRIBUTIONS TO THE CYTOLOGY OF THE BACTERIA. 479 



Do B a c i 1 1 a r Forms av i t li a Vesicular Nucleus 

 exist? — I have already had occasion to note that Bacilli 

 with a typical vesicular nucleus have never come nuder my 

 observation. All the oi-ganisms which I fonnd to be con- 

 stituted in this manner have proved to be Fungi. Others, 

 however, have described very definite instances in which 

 vesicular nuclei occur, and the matter is of such moment that 

 a brief discussion is here necessary. 



In the accounts of the older observers, the observations 

 are so incomplete, and the technique employed was so 

 imperfect, that a discussion seems useless. This is not the 

 case with some more recent work, however. I refer to the 

 publications of the Bohemian investigators, Vejdovskv, 

 Mencl, and Rayman and Kruis. 



There seems no doubt at all, from the very careful work 

 of Vejdovskv (1900, 1904) and Mencl (1907), that the organ- 

 ism which the former has named Bacterium gammari 

 really possesses a vesicular nucleus, which divides mitotically.^ 

 The only point which requires to be settled is whether the 

 organism really belongs to the Bacteria or not. Considerable 

 discussion has already taken place regarding this. Some 

 observers (e.g. Guilliermond, 1907, 1908, 1910) are inclined 

 to regard it as a yeast-like fungus — not a Bacterium at all. 

 The resemblance between certain yeast forms and this 

 organism is certainly very striking (compare, for example, 

 the figures of Mencl [1907]— figs. 4, 7, 10, etc. [pi. x] — 

 with Wager's [1898] figures— figs. 45, 46,47 [pi. xxx]— of 

 Saccharomy ces pas tori an us). After my own experi- 

 ences with Bacterium-like yeasts (see p. 455), I hesitate to 

 express an opinion Avith regard to B. gammari. It is 

 most important that further observations should be made 

 upon this most interesting organism ; and it is to be hoped that 



^ My friend Prof. Vejdovsky Las very kindly given me a j^reparation 

 of this organism, so that I have been able to examine it myself. To 

 my mind there can be no doubt as to the accuracy of the accounts 

 which have been given of it. 



