1016 SUMMARY OF CUHRENT RESEARCHES RELATING TO 



aimlogoiis manner to tlio foregoing, is referred to chiefly to show that 

 the author's own measurements differ from those of Chcyne and Cheshire; 

 the former gives 1 • 77;u, length of spore and • 90/:i, hreadth, while the hitter 

 for the same give 2-12^ and 1-07/x. The breadth of cell in Canada 

 balsam as given by Cheyne and Cheshire = 0"83 p. and by Koch as 

 0'73/ji. Notwithstanding these discrepancies, the author consid(:rs that 

 the bacillus he investigated Avas undouLtedly the same as that described 

 by Cheshire and Cheyne as BaciUus alvei, the cause of foulbrood in hive 

 bees. 



jB, Brassicse Pommer resembles B. caroiarum in appearance, but it is 

 distinguished therefrom by the greater tliiokness of the spore-membrane, 

 by the closer growth of the filaments, and by the appearance of granules 

 and ill-defined dark spots about the period of spore-formation. 



Supposed Spores of the Typhoid Bacillus.* — When Gaffky found 

 certain spheroidal bodies, highly refracting, situated at the extremities 

 of the typhoid bacillus, and characterized also by their resistance to 

 auilin dyes, he came to the conclusion that these polar bodies were 

 spores. This conclusion is erroneous, says Dr. H. Buchner, for these 

 polar bodies are wanting in three characteristics of the true endogenous 

 spores, namely, the resistance to dyes, resistance to drying, and their 

 power of germination. In one respect, however, they do resemble spores ; 

 that is, in being composed of thickened plasma. 



The conditions under which the polar bodies appear in the typhoid 

 bacillus are limited apparently to the acidity of the nutrient medium 

 and the withdrawal of oxygen during cultivation. These the author 

 regards as producing a condition of degeneration, of which the polar 

 bodies are the result. Gaffky had said that these polar bodies w'cre insus- 

 ceptible to anilin dyes. Quite the contrary, says the author, for these 

 bodies not only take up the dye most strongly, but also retain it longer 

 than the rest of the cell after the action of decolorants. This, he says, 

 is easily shown if a watery solution of gentian-violet be gradually added 

 to a fresh preparation. But if stained on a cover-glass in the usual 

 manner they are not to be seen. Hence, says the author, these polar 

 bodies are due to a retraction of the plasma. 



This retraction is produced either as the result of the drying of the 

 cover-flass or by the dye (gentian-violet) acting as a poison. For with 

 other non-poisonous or less poisonous dyes (as phloxin-red), no retraction 

 or staining is observable. 



On the whole, the author thinks these polar bodies consist of cell- 

 plasma in a somewhat thicker condition than the rest of the cell-contents 

 because of their affinity for dyes, and also on account of their refraction 

 in the fresh condition. 



Spore-formation in the Bacilli of Xerosis conjunctivae, Strepto- 

 cocci, and Cholera spirilla.f — Dr. Keisser thinks that the xerosis 

 bacilli are probably not the specific contagion of xerosis conjunctivae, as 

 was maintained by Ernst, because he has come across other micro- 

 organisms which are morphologically i<lentical with this bacillus. 



The organism in question is a small thin mobile rod divided into two 

 parts by a clear space, and it propagates by division through the clear 



* Cintralbl. f. Bi.kteriol. u. riuuslteuk., iv. (1888) pp. 353-8, 3S0-90 (1 pi.), 

 t Zeits.-hr. f. IIygi..n.', iv. (1888) pp. 2G8-97. 



