2068 Journal of Applied Microscopy 



Fedorowitsch. Ueber die Kornigkeit derBak- The method adopted by this author for 

 terien. Cent. f. Bac. u. Par. II, 8 : 481, igo2. ^ 1 r ,, • ^ , , , 



Study of the internal structure of bac- 

 teria is as follows : 

 The bacteria are very carefully spread out upon a cover slip and treated for 

 5-10 minutes with saturated anilin water-gentian solution, washed quickly with 

 water and then treated for one minute with Gram's iodine solution, and again 

 washed in water. They are then treated for 1-2 minutes with one-half or one 

 per cent, safranin water solution, and a third time washed in water. They are 

 then dried and treated with a mixture of anilin oil and xylol until properly 

 decolorized. By this means the contents are differentiated, parts being colored 

 strong violet, while the greater part of the body is colored a rose color. Some 

 excellent figures show the results. He finds that spore bearing bacteria have a 

 peripheral row of granules which become spores ; while non-spore bearing bac- 

 teria show similar granules which do not form spores. H. w. c. 



MQore. The Isolation of the Typhoid Bacil- The author has given a contribution to 

 lus. British Medical Journal, p. vo-?, IQ02. ^, , 1 1 1 • . r .1 ■ 



-^ ^ the much worked subject of the separa- 



tion of the typhoid and colon bacillus. He gives two methods, one of which is 

 dependent upon the motile property of the typhoid bacillus, but which he finds 

 not to be practical. The second, which he thinks is very useful, depends upon 

 the use of Eisner medium, which he modifies by the substitution of agar for gela- 

 tin. The method is as follows : 



Modified Eisner agar medium. Take 5U0 grams of potatoes, peel them and 

 scrape them on a grater. The pulpy mass so obtained is then macerated in a 

 liter of water for 3 or 4 hours ; strained and allowed to stand over night. The 

 next morning the clear supernatant liquid is decanted and the volume made up 

 to a liter. This liquid is rendered alkaline and 20 grams of agar added. The 

 process is then continued as for ordinary agar. When sterile the medium is 

 distributed in test tubes, and immediately before using .5 c. c. of the following 

 solution is added to each tube : 



Potassium iodine - - - - 10 grams. 



Water - - - - - - 50 c, c. 



The medium should be used fresh. 

 Plates prepared with this medium and sown with mixtures of typhoid and colon 

 bacilli are incubated for '24 hours at 87°. At this time an examination with a 

 low power will show an evident and characteristic distinction between the typhoid 

 and colon bacilli. By the use of this method he is not only able to separate the 

 two organisms in artificial mixtures, but has been able to find the typhoid bacil- 

 lus in cockles which were suspected as having been the cause of the outbreak of 

 typhoid fever, h. w, c 



Bariekow. Beitrage zur Differentialdiagnose The author uses one culture medium 

 des Typhus bacillus. Wien. Klin. Rund. composed of peptone or nutrose 1 per 

 No. 44, 1 90 1. ^ ^ ^ '^ 



cent., milk sugar 1 per cent., NaCl 5 



per cent., distilled water 100 c. c, and a second in which grape sugar is substi- 

 tuted for the milk sugar. In 24 hours' growth the coli bacillus shows a strong 

 acid reaction upon both media, but grows more rapidly upon the second, while 

 the typhoid bacillus produces acid in the second but not in the first medium. 

 The author always succeeds in differentiating the two in 24 hours, h. w, c. 



