762 SUMMARY OF CURRENT RESEARCHES RELATING TO 



produced by it are very similar to those of true tuberculosis. The author 

 also found that the animals affected with the disease react to avian tuber- 

 culin in the same way as a tuberculous animal reacts to tuberculin. 



Morphology and Biology of the Whooping-cough bacillus.* — W. N. 

 Klimenko has studied the whooping-cough bacillus of Bordet and 

 Gengou. The organism appears as small round-ended non-motile rods, 

 occasionally arranged in pairs united at their extremities, and also in 

 chains when grown in milk ; the rods are larger when grown in fluid than 

 in solid media ; involution forms are rare, but occur in pepfon-water ; 

 the bacillus has no capsule and does not form spores ; it does not stain by 

 Gram's method, and is not acid-fast ; it stains a lilac tint with methyl- and 

 toluidin-blue ; bipolar staining is best shown with carbol-toluidin-blue. 



The organism is obtained in greatest numbers during the catarrhal 

 phase, or the first week of the spasmodic stage of the disease ; cultiva- 

 tions are made from sputum, washed with sterile salt solutions, and spread 

 on plates of potato-glycerin-blood-agar ; the colonies, which apjaear after 

 2 days' incubation, are round, colourless, and ref ractile, and show a strong 

 hemolytic action ; with glucose and glycerin there is no production of 

 gas ; on gelatin it forms a grey opalescent growth, and does not liquefy 

 the medium ; on potato the growth is shining and greasy and of a brown 

 colour ; in ordinary broth there is clouding and a production of slime ; 

 on 1 p.c. pepton-water growth is less vigorous and no slime is formed ; 

 when grown on milk the medium becomes cleared, of a yellow or yellow- 

 brown colour, and strongly alkaline ; there is no indol formation ; the 

 organism appears to form an endotoxin pathogenic for young dogs, cats, 

 monkeys, mice, guinea-pigs, and pigeons, but less so for rabbits, goats, 

 horses, and for full-grown dogs and cats. Immune sera obtained from 

 rabbits and dogs had but slight active agglutinating properties. Cultures 

 retained their vitality for a month on blood media, 10 to 14 days on 

 gelatin, 3 to 4 weeks on agar, and in broth for 30 to 40 days. 



Life Cycle of Bacillus Nitri sp. n.f — A. Ambroz isolated this 

 organism on gelatin plates prepared to isolate Saccharomycetes from a 

 5 p.c. solution of sodium nitrate ; the author regards the organism as a 

 new species. It appears as stout rods 3-8 //. long, and width about one- 

 third of the length ; in broth it is shorter and stouter ; on potato and 

 on solid blood serum long, thin, thread-like forms are met with ; it 

 produces a yellow-brown pigment in its late development, especially on 

 potato, but also on agar and sugar-agar.; on gelatin it forms white 

 regular kidney-shaped colonies, the medium being quickly liquefied ; 

 growth on Endo's medium has a faint rose colour ; it does not grow 

 on Drigalski's medium ; in milk it produces acid, but there is no clotting ; 

 in broth it forms a slight pellicle, and also a sediment ; the optimum 

 temperature is between 35° C. and 47° C. ; when grown on potato it 

 has a strong tendency to form spores. 



The method of observation employed by the author consisted in 

 fixing with HC1 2 solution, staining with Giemsa's stain for about an 

 hour, and thoroughly decolorising with alcohol. In the early develop- 

 mental state the bacillus has a homogeneous appearance ; in agar cultures 

 the rods multiply by division, which commences by the formation of 



* Centralbl. Bakt., lte Abt. Orig., li. (1909) p. 305. f Tom. cit., p. 193. 



