378 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fuchsin-Agar as a Diagnostic Medium for Typhoid Bacteria.* — 

 D. S. Petkowitsch recommends a medium with the following composition 

 for differentiating Bacillus typhosus from B. coll and allied organisms. 

 1000 grrn. neutral agar (:» p.c.) ; 10 grm. (1 p.c.) milk-sugar ; 5 c.cm. 

 '(0*5 p.c.) alcoholic solution of fuchsin ; 25 c.cm. (2*5 p.c), 10 p.c. 

 sodium sulphite solution ; 10 c.cm. (1 p.c), 10 p.c. soda solution. 



The alkalinity should be at least ' 1 p.c ; usually it amounts to 

 0*1-0 "15 p.c pure soda, titrated with litmus paper as indicator. On 

 this medium the typhoid colonies are colourless, while those of the 

 Volt group are red or reddish in from 15 to 24 hours. 



Cultivation of the Leishman Body.f— J. C.B.Statham successfully 

 cultivated the Leishman bodies from a case of Dum-Dum fever in 

 ■citrated blood, obtained from the spleen and liver. Apparently about 

 4 c.cm. of blood was mixed with 1 c.cm. of 4 p.c. solution of sodium 

 citrate, and the tubes incubated at 20° C. 



Subcultures on the same lines were also successful, but the life-period 

 of the cultivated parasite appears to be limited to 14-21 days. 



The ordinary body is roundish, with macro- and micronucleus ; after 

 a period of growth the body elongates and develops a flagellum in the 

 vicinity of the micronucleus. The motility of these flagellated forms is 

 sluggish, and the parasites advance with the flagella end foremost. 

 The flagellated parasites may give rise to spirillar forms by a process of 

 unequal longitudinal fission. 



Use of Acid Media in Isolation of the Plague Bacillus.J — 

 W. C. C. Parkes and F. H. Joseph find that by the use of acid media 

 the growth of pneumococcus is inhibited in cultures of sputum of cases 

 affected with plague. By this means the pneumococcus has been 

 eliminated, and the animals which had been inoculated with acid broth 

 culture died of plague infection. 



Bacteriology of Plague.§ — H. Watkins-Pitchford makes the following 

 interesting observations on the plague bacillus : (1) The Bacillus jwstis 

 grows vigorously between 15° C. and 40° C, showing the ease with which 

 the organism can adapt itself to the varying seasonal temperature. 

 (2) Growth of the bacillus seems to be almost inhibited in carbonic 

 dioxide. (3) After 50 days' culture in bouillon, with 2*5 p.c. sodium 

 chloride, the plague organism is incapable of further growth when re- 

 transplanted upon other media. (4) The same observation held true 

 after a lapse of 75 days for glucose agar and glucose bouillon. (5) After 

 100 days, however, the cultures on glycerin agar, ox serum, salt agar, 

 glycerin bouillon, and plain bouillon proved fatal to guinea-pigs. (6) An 

 animal may retain plague bacilli alive within its tissues and not manifest 

 signs of the disease. This was proved by an experiment in which an 

 inoculated rat showed no signs of illness, but when, after 23 days sub- 

 sequent to inoculation, the rat was killed, a drop of pus was found in a 



* Centralbl. Bakt. Orig. l'«> Abt., pp. 304-12. 



t Journ. Roy. Army Med. Corps, iv. (1905) pp. 13-15, 321-34 (1 pi. and 2 rigs.). 

 X Brit. Med. Journ. (1905) i. p. 130. 



§ Report on the Plague in Natal, 1902-3. By Ernest Hill. London, Cassell 

 and Co., 1904, 192 pp., with map, charts, and photomicrographs. 



