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SUMMARY OF CURRENT RESEARCHES RELATING TO 
means of a small Land air-pump, the volume of air being measured 
by the displacement of water in a flask. Having taken the sample 
(5-20 litres), the wool plug is replaced in the neck A. The pow- 
dered sugar is then shaken down into the wide part of the tube A B, 
and 15 ccm. of melted sterile nutrient gelatin are poured in. The pow- 
dered sugar readily dissolves in the melted gelatin, and when solution 
is complete a roll-culture is made in the tube, just as in Esmarch’s 
method. The tube is then placed in an incubator at 20° C., and the 
colonies are allowed to develop. 
Cultivation of Tetanus Bacillus.* — Dr. R. T. Hewlett cultivates 
tetanus bacillus in yeast flasks of about 90 ccm. capacity, three parts filled 
with 2 per cent, grape sugar bouillon. The neck is plugged with a 
perforated rubber stopper through which a glass tube passes to the 
bottom of the flask. The upper end of this, and the side tube also, are 
stuffed with cotton wool. The apparatus is first sterilized and then 
inoculated. After this the vertical tube is connected with a hydro- 
gen generating apparatus, and when the whole flask is filled, the end of 
the side tube is plunged in a vessel filled with mercury, and the free end 
of the vertical tube sealed off in the blowpipe flame. 
Cultivating Anaerobes in Agar.j — Dr. R. T. Hewlett cultivates 
anaerobes in narrow test-tubes, three parts filled with 2 per cent, sugar- 
agar. The tubes are steamed for a few minutes in a sterilizer to get rid 
of dissolved oxygen, and then cooled in water. When the agar has set, 
the inoculations are made well into the depth of the medium. The in- 
oculation puncture is then sealed up by heating the tube in a flame, so 
as to melt the suj)erficial layer of the agar. The upper part of the 
tube is heated, and a well-fitting rubber cap applied while the tube 
is still hot. 
Heating Arrangement of the Microscope for Bacteriological Pur- 
poses.;!: — Herr P. Friedrich describes a new heating arrangement for the 
Microscope. An air-bath, in which the Microscope stands, is the chief 
feature of the arrangement. This air-bath is closed in front by a glass 
plate, and is kept at a temperature of 37° by a water-jacket, .heated from 
below. The temperature is regulated by means of a Meyer-Reichert 
regulator. 
(2) Preparing: Objects. 
Simple Method for Producing two or more Embryos from one 
Egg.§ — Herr J. Loeb experimented with eggs of Arbacia which were 
artificially fertilized in normal sea-water. Ten minutes after fertiliza- 
tion they were removed to sea- water and distilled water in equal volumes ; 
the membrane was destroyed by endosmosis, and part of the protoplasm 
•escaped. The egg now consisted of two connected spheres of proto- 
plasm which contained one nucleus between them. If, after some time, 
the eggs were returned to normal sea-water, each of the two spheres 
developed into a completely normal and perfect embryo. His experi- 
ments show that an embryo can arise simultaneously from each part of 
* Lancet, July 14, 1894, p. 73 Cl fig.)- t P. cit. 
J Internat. Med.-photogr. Monatschrift, i. (1894) p. 30. See Arb. d. Kais. 
Gesundheitsamtes, viii. (1892). 
§ Arch. f. ges. Physiol., lv. (1894) pp. 525-30. See Zool. Centralbl., i. (1894) 
p. 346. 
