834 SUMMARY OP CURRENT RESEARCHES RELATING TO 



tact with air still blue. When the tube was shaken up, the whole of the 

 fluidified gelatin became blue. The return of the blue obviously depended 

 on the inclosed air, for it disappears almost completely if the fluid be kept 

 from contact with air by pouring oil over it. (2) Meat-peptone-agar pos- 

 sesses an advantage over the foregoing in that it does not reduce the 

 methylen-blue. For staining, one-third of a tube full of this medium with two 

 drops of a watery sterilized concentrated solution of methylen-blue were em- 

 ployed. After sterilization and inoculation with the potato-grown bacillus, 

 there appears, after about three days at a temperature of 22°, a decoloration 

 of the superficial layers of the agar, and this in six days amounts to about 

 1*5 cm., while the colony itself seems slightly blue. The loss of colour 

 proceeds more rapidly than the growth of the vegetation, and the decolorized 

 gelatin is, as is shown by microscopical examination and inoculation, free 

 trom bacteria. 



Numerous bacteria were found to be incapable of reducing either of 

 the dyes, and the author believes from this that he has hit upon a way 

 of ascertaining certain chemical relations between bacteria and nutrient 

 media. 



Heydenreich, L. — Sterilisation mittels des Dampfkochtopf (Papin'scher Topf) fiir 

 bacteriologische Zwecke. (Sterilization by the steam digester (Papin's digester) for 

 bacteriological purposes.) 



[The author iinds that a nutrient fluid placed close to the source of heat, io the 

 water, quickly acquires the surrounding temperature of the superheated steam, 

 if only the walls of the glass vessels be not too thick, the air as far as possible 

 removed, and the quantity of the nutrient fluid not too great. And also that as 

 no bacteria or fungi can withstand steam at a temperature of 120° for 5-10 

 minutes, it may therefore be considered that 15-20 cc. of fluid is safely sterilized 

 if the thermometer keeps at 120° for 5-10 minutes, and if the air has been 

 previously carefully removed (the manometer marking two atmospheres.)] 



Zeitschr.f. Wiss. Mikr., IV. (1887) pp. 1-24 (4 figs.). 

 Kellicott, D. S. — Notice of some Fresh-water Infusoria, with remarks on collecting 

 and preserving these delicate animals. 



Microscope, VII. (1887) pp. 225-33 (4 figs.). 

 N A s M Y T H, T. G. — Methods for cultivation of micro-organisms from water. 



Sanit. Record, 1887-8, pp. 16-9. 

 E H R n E c K, H. — Ueber stdrende Einflilsse auf das Constanthalten der Temperatur bei 

 Vegetationsapparaten und tlber einen nenen Thermostaten. (On disturbing in- 

 fluences on the constancy of the temperature in culture-apparatus, and on a new 

 thermostat.) 



Centralbl. f. Bacterlol. u. Parasitenk., II. (1887) pp. 262-5, 286-90 (3 figs.). 

 V I G N A L, W. — Sur un moyen d'isolation et de culture des microbes anaerobies. (On a 

 method of isolation and culture for anaerobic microbes.) 



Ann. Instit. Pasteur, 1887, pp. 358-9. 

 WiLFARTH, H. — Ueber eine Modification der bacteriologischen Plattenculturen. (On 

 a modification of the bacteriological plate-cultures.) 



Deutsche Med. Wochenschr., 1887, pp. 618-9. 

 Zaslein, T. — Ueber den praktischen Nutzen der Koch'scben Plattenculturen in der 

 Cboleraepidemie des Jahres 1886 in Genua. (On the practical use of Koch's plate- 

 cultures in the Genoa cholera ei^idemic of 1886.) 



Deutsche Medicinische Ztg., 1887, pp. 389-91. 



(2) Preparing' Objects. 



Methods for killing Invertebrata.* — For the preservation of animals, 

 Prof. F. E. Schultze j)oints out, it is desirable that they should seem as 

 lifelike as is possible, or that no changes should occur to prevent them from 

 being useful for fine microscopical work. Care must be taken to fix the 

 animal in the extended condition, and to prevent the tendency to contrac- 



* Tafieblatt 59 Versamml. Deutscher Naturf. u. Acizte, 1886, pp, 411-4. Cf. Biol. 

 Centralbl.. vi. (18bi7) pp. 760-4. 



