342 SUMMARY OF CURRENT RESEARCHES RELATING TO 



in broth cultures. It liquefies gelatin and produces haemolysis in blood- 

 agar. It grows with great rapidity upon artificial media, and quickly 

 covers the surface of an agar slope. Thus it can easily be obtained in 

 pure culture. It produces in broth-cultures a toxin highly virulent to 

 laboratory animals. 



Bacterial Flora of Putrefying Intestine.* — A. Distaso has carried 

 out investigations of portions of human intestine received from the 

 post-mortem room, and allowed to putrefy at room temperature or at 

 37° 0. The samples were obtained from young children, adults, and 

 persons advanced in life. In this preliminary communication the author 

 mentions the types of bacterium encountered. He describes three 

 phases of putrefaction. In the first phase— that of reduction of the 

 intestinal flora — the material becomes very alkaline, and the odour of 

 scatol is replaced by that of butyric acid. The second stage, in which 

 B. putrificus coagulans is the predominant form, is the phase of anaerobic 

 ferments. The third, or ammoniacal phase, is that in which strict 

 aerobes develop and transform complex bodies into simple products, 

 causing total disintegration of the material. Speaking generally, the 

 flora of the putrefying intestinal wall is similar to that of meconium — a 

 circumstance which suggests that some organisms remain established in 

 the intestine throughout life. 



Anaerobes of the Normal Human Intestine.! — P. Detono describes 

 certain types of anaerobic bacteria isolated from the intestines or from 

 f feces. These organisms are classified as proteolytic or peptolytic bacilli, 

 the first two organisms to be mentioned belonging to the former group. 

 B. sporogenes coagulans is a slightly motile, Gram-positive organism, 

 showing a striking uniformity in the size and shape of the bacilli. They 

 are straight rods about the size of anthrax baci'lli. The spores are oval 

 and generally subterminal. B. putrificus ovular is shows greater variety 

 in size, appearing in the form of straight or curved rods, motile and 

 Gram-positive, and forming oval terminal spores. The peptolytic bacilli 

 include B. fissus, which presents occasionally a beaded appearance; 

 B. anaerobicus aJraligeyies, which are non-motile, forming terminal 

 spores ; B. tortuosus, a variable organism, which may appear as straight 

 rods or grow in chains ; and B. regularis ftJiformis, non-motile and 

 Gram-positive, a slender filamentous organism, which may attain a 

 length of 30-40 ^l. 



Life-history and Morphology of Azotobacter Chroococcum.| — A. 

 Prazmowski sums up the results of his studies upon this organism. It 

 is dimorphic, appearing in the vegetative stage as a bacterium, and in 

 the stage of fructification as a micrococcus. Under favourable con- 

 ditions the organism is motile until the stage of spore-formation. 

 Young forms are more active than older ones. The flagella are long 

 and arranged in peritrichous fashion, but disappear towards the end of 

 the vegetative stage, being replaced in the micrococcus form by a single 



* Centralbl. Bakt., Ite Abt. Orig., Ixii. (1912) pp. 219-29. 

 t Centralbl. Bakt., Ite Abt. Orig., Ixii. (1912) pp. 229-34. 



X Bull Internat. Acad. Sci. Cracovie (1911) 10 B, pp. 739-41 ; Centralbl. Bakt., 

 2te Abt., xxxiii. (1912) pp. 292-305. 



