ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 747 



the rubber tube between A aud B by means of a Pasteur pipette ; if the 

 material is solid it is suspended in a small quantity of sterile fluid. 



New Method for Closing Cultivation Tubes.*— G. C. Chatterjee 

 states that cotton-wool plugs are not suitable for stopping test-tubes in 

 tropical climates, as they soon get overgrown with fungi, etc. He has 

 found that if the one tube be covered by means of another of slightly 

 larger diameter, and kept in its place by means of a spring attached to 

 a ring on the lower tube, many advantages accrue and the disadvantages 

 are obviated. 



New Method for the Cultivation of Anaerobic Bacilli.f — N. Pende 

 and L. Viviaui employ an apparatus for the cultivation of anaerobic 

 bacilli, which consists of a small glass tube closed at both ends aud 

 containing rarefied hydrogen gas ; one end of this tube is drawn out 

 into a fine point ; this point is broken under the surface of the culture 

 fluid, some of which is draAvn up into the tube, which is now closed 

 again by a flame, and placed in a thermostat. 



Aerobic Culture of Essential Anaerobes.| — A. Wrzosek has found 

 that the substance existing in animal and vegetable tissues that favours 

 the aerobic growth of essential anaerobes was not affected by exposure 

 to high temperatures, but exposure to the air destroyed the active pro- 

 perties of this substtmce. A series of tubes were taken, each containing 

 10 c.cm. of ordinary neutral broth, and into each was introduced fresh- 

 cut cyhnders of potato or animal tissue weighing 2 grm., and into some 

 of the tubes melted paraffin was then poured ; the whole were sterilised 

 at 120° C. for 15 minutes. Some tubes were placed in the dark, and 

 others exposed to the action of the hght. After an interval of time the 

 tubes were inoculated with broth cultures of the same anaerobic organism, 

 and incubated at 37^ C. The results showed that the medium in those 

 tubes tliat were not closed by paraffin were altered, whereas the medium 

 in the closed tubes remained active even for over 101 days, so that the 

 air and not the light was the agent for destroying the medium for the 

 culture of anaerobes. Previous drying of the portions of animal or 

 vegetable tissue had no effect as regards the culture of some anaerobic 

 organisms, but with others the growth was not so good, and as in the 

 case of the tetanus l)acillus no spores were formed. 



The author also obtained cultures of anaerobes when plant seeds, 

 such as barley grains, were substituted for the potato or animal tissue 

 in the culture tubes. The sulistance that favours the aerobic growth of 

 anaerobes was also demonstrated in wood charcoal, coal and coke, but 

 the growths were not vigorous and spores were not formed. The presence 

 of this substance was also demonstrated in chalk, zinc, and iron. It has 

 long been known that anaerobes can develop in ordinary broth, if an 

 aerobe is simultaneously grown in the same tube, a fact explained ])y 

 Pasteur as due to the absorption of the oxygen by the aerobe. The 

 author has shown that potato, charcoal, etc., all possess a high degree of 

 reducing power, though with chalk, fresh potato, and zinc this only 

 occurs to a slight degree. 



* Lancet, 1907, ii. pp. 1083-4 (1 fig.). 



t Centralbl. Bakt., Ite Abt., Orig., xliv. (1907) p. 282. J Tom. cit., p. 607. 



