3:^8 SUMMARY OF CURRENT RESEARCHES RELATING TO 



treated should be about ' 5 to 1 c.cm. in size. If casual contamiuation 

 has crept in, the broth becomes turbid within three days. Visible growth 

 of tubercle bacilli usually starts after one or two weeks. 



New Medium for Cultivating' the Tubercle Bacillus.* — G. Valletti 

 has devised the following medium on which he has obtained a growth 

 of tubercle bacilli in 2 4-0 6 hours. It is composed of ordinary agar 

 with bouillon and sodium chloride, but without glycerin. To this are 

 added 2 c.cm. of cow's milk serum, obtained by acidulating milk with 

 a few drops of acetic acid and then boiling it. 



New Cultivation Medium. f — A. Rochaix reports most excellent 

 results from the use of the following medium. The juice of carrots 

 {Daucus carota) is obtained by pressure. To 800 c.cm. of the juice 

 200 c.cm. of water are added. To agar prepared in the usual way, the 

 juice is added in the proportion of 30-:^5 grm. to 1000 c.cm. of the 

 dihited juice. The mixture is heated in the autoclave at 115° for 20-25 

 minutes. Xext it is cleared with white of egg, alkalinized and filtered. 

 After distribution in tubes it is re-sterilized at 108-110°. 



The author mentions a number of organisms cultivated in this 

 medium most successfully. It does not favour the growth of staphylo- 

 cocci, Loeffler's bacillus, and pneumococcus. 



The addition of 10 p.c. neutral glycerin at 80° to the foregoing 

 medium favours the growth of fungi. The luxuriant growth of the 

 bacillus of tubercle on the glycerinated medium is noted. This medium 

 also serves to distinguish members of the coli-typhoid group and allied 

 bacteria. Thus the coli group forms gas while the typhoid does not. 

 The other non gas-forming bacteria are B. enteritidis and B. fsecahs 

 alkaligenes. 



Deep Sea Bacteriological Water-bottle. if — I). J. Matthews describes 

 a water-bottle which has been used down to 800 fathoms with complete 

 success. For the details of construction and working, the original 

 should be consulted. 



Tests for Human and Bovine Tubercle. § — J. Fraser remarks that 

 there are three tests which give trustworthy evidence of the type of 

 bacilli. 1. Theobald Smith's test. This is glycerin bouillon, to which 

 0*05 acid is added. In the case of the human bacillus, the degree of 

 acidity progressively increases, while the bovine bacillus diminishes the 

 acidity, and the medium may even become alkaline. 2. Gobbet's test. 

 In this 4 p.c. glycerin is added to Dorset's ^gg medium. On this the 

 l)Ovine bacillus grows scantily if at all, while the human bacillus spreads 

 rapidly and profusely. 3. The most reliable test is that termed the 

 animal test. It is found that the bovine bacillus is extremely virulent 

 for the rabl)it and the calf. If the animal be inoculated with the 

 human bacillus, the disease is limited to a few chronic lesions in the 

 internal organs. If inoculated witli bovine tubercle the animal rapidly 

 emaciates, and usually dies in six weeks from acute miliary tuberculosis. 



» Centralbl. Bakt., Ite Abt. Orig., Ixviii. (1913) pp. 239-41. 



t C.R. Soc. Biol. Paris, Ixxiv. (1913) pp. 604-7. 



X Journ. Marine Biol. Assoc, ix. (1913) pp. 525-9 (4 figs.). 



§ Brit. Med. Journ. (191-3) i. pp. 760-2. 



