86 SUMMAKY OF CURRENT RESEARCHES RELATING TO 



nitrogen of nitrates into free nitrogen, and the gums produced by both 

 these organisms are identical. The slime is simply the capsule of the 

 organism that has become swollen ; thus the formation of bacteroids 

 depends on the chemical nature of the capsules of the bacteria, and is 

 not connected with any fixation of nitrogen that may occur within the 

 plant. Probably the plant is able to use the bacterial slime to build up 

 its nucleoprotein. The symbiosis between host and bacterium relates to 

 the alteration of carbohydrates and not to the fixation of nitrogen. The 

 function of the micro-organism in the nodule is to produce slime which 

 is closely related to the carbohydrates of the nucleoproteid molecule of 

 the plant. 



Direction of Growth of Bacteria in Gelatin.* — H.. C. Jacobsen 

 from observations on B. zopfii finds that the direction of the mathe- 

 matical curves of growth of the thread forms in gelatin, is that of the 

 resultant tension, and perpendicular to the pressure strain, and that this 

 organism has a property of reacting by an elastic tension to which the 

 author gives the name of " Elasticotropie." 



Cultivation of Tubercle Bacilli after Disinfection by Formaldehyde 

 and by Singeing-.f — C Spengler obtained growth of tubercle bacilli from 

 sputum after exposure to 48 hours action of formahn, all accompanying 

 bacteria being killed. Disinfection by singeing consists in the partial 

 sterilisation of the sjmtum l)y heat : portions the size of a hazel nut held 

 on a platinum looj) are passed through the flame, and inoculations are 

 made on blood-agar, or glycerin-agar. The author points out that the 

 inactivity of the bactericidal function of the leucocytes in the sputum is 

 to be considered. 



Streptococcus capsulatus gallinarum.| — Dammann and Manegold 

 isolated from the body of a fowl dead with appearances of haemorrhagic 

 septicaemia, a capsulated streptococcus. The immber of cocci in a chain 

 varied according to the medium from 80-100 ; individual cocci measured 

 (»*8 /t-(i"5 /x ; motility was absent; the capsule was only manifest in 

 those streptococci grown in the animal body. Growth was aerobic and 

 anaerobic, good on blood senim and in milk, but less on meat extract, 

 broth, gelatin-, and agar ; acid and small amounts of indol are formed in 

 saccharose broth ; gelatin is not liquefied ; it is very susceptible to drying 

 by heat and to the action of antiseptics. 



Incubation of the inoculated disease varied from 6-80 days, in one 

 case as long as 60 days. It is pathogenic for rabbits and mice, and 

 especially for pigeons ; dogs, ducks, and guinea pigs are not susceptible. 



J]tiology of Syphilis.§ — ^\ . Miihlmauu finds that the Gytorrhyctes 

 hit's is not a flagellated protozoon, but represents neutrophil granules of 

 leucocytes. He proposes to name them " Granulocytes." 



Morphology of Spirochaeta pallida. 1| — M. Forest advocates the 

 following method for examination of Spirochaeta?. The tissue fluid is 



* Centralbl. Bakt., 2te Abt. xvii. (1906) p. 53. 



t Op. cit., Ite Abt. Ref. sxxix. (1906) p. 24. J Tom. cit., p. 60. 



§ Op. cit., Ref. xxxviii. (1906) p. 745. 



II Op. cit., Ite Abt. Orig. xlii. (1906) p. 608. 



