no 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
concerned with the best modes of treatment of a great variety of 
botanical preparations and tissues, and with the demonstration of pro- 
cesses of botanical physiology, which it takes up in succession and in 
considerable detail. The work under review is rather a guide to the 
use of the Microscope by botanists, applicable to the whole scope of his 
investigations, and may be regarded as a supplement or companion to 
Strasburger’s work. The first section is concerned with the Microscope 
as an instrument, and with microscopical appliances, and contains nothing 
that will not be found in ordinary English text-books. The second and 
larger portion is a guide to the preparation of botanical objects for the 
Microscope, and treats the subject more in detail than do English 
treatises, including the most recent methods recommended by the best 
workers. Here will be found directions for hardening, fixing, clarifying, 
and softening, the preparation of botanical sections, the use of staining 
materials, the preservation of the sections when made, and similar daily 
needs of the microscopical botanist. For the fixing of algfse, and of the 
protoplasmic contents of the higher plants, Ripart’s fluid is recom- 
mended, consisting of 0*3 grm. cupric acetate, 0*3 grm. cupric chloride, 
1 ccm. glacial acetic acid, 75 ccm. camphor-water, and 75 ccm. distilled 
water ; for studies of the cell-nucleus a very dilute solution of gentian- 
violet, 0*3 grm. dissolved in 100 ccm. of absolute alcohol, and this again 
diluted with 1000 times its volume of distilled water. 
Cl) Collecting: Objects, including- Culture Processes. 
Preparing Nutrient Bouillon for Bacteriological Purposes.*— 
Herren Petri and Massen give the following for preparing bouillon : — 
Fresh chopped meat containing little fat is soaked for one hour in the 
necessary quantity of distilled water. It is next heated for three hours 
at about 60° C., after which it is boiled for half an hour and filtered. 
When cold the degree of acidity of the fluid is tested from samples of 
10-20 ccm. As a rule 10 ccm. require by the litmus reaction 1*8 ccm. ; 
by the phenolphtalein reaction, 3 ccm. of 1/10 normal caustic soda 
solution. The broth obtained from the meat of different animals did not 
present any striking differences. After the addition of alkali pepton 
and salt it is boiled for some time, best over the open fire for a quarter 
of an hour, and then filtered hot. Too long and too frequent boiling 
are to be avoided. The bouillon and the medium prepared from it are 
to be. kept in the dark. 
Degree of Alkalinity of Media for Cultivating Cholera Bacilli. t— 
Dr. M. Dahmen made a series of experiments to determine the most 
suitable degree of alkalinity for the cultivation media of cholera bacilli. 
From them he concludes that for the examination of faeces for cholera 
bacilli a gelatin with 1 per cent, of soda is the most suitable, and that 
a faintly alkaline medium is not only not sufficient, but absolutely 
unsuitable. 
Method for Sowing Bacteria on Gelatin Plates and other Surface 
Media.J — Hr. P. Troppau practises the following device for sowing 
* Arbeiten aus d. Kaiserl. Gesundheitsamte, viii. No. 2. See Centralbl. f. 
Bakteriol. u. Parasitenk., xii. (1892) p. 484. 
t Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) p. 620. 
X Tom. cit., pp. 653-4. 
