358 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



diverticulum till the later nymphal stages. Here they maturate, after- 

 wards migrating to the intestine of the adult insect, even when kept 

 devoid of food. Cultivations in artificial media from the insect in any 

 stage of development was found to be almost impossible, owing to some 

 special conditions. The passage from this special condition to one 

 purely saprophytic appears to be due to changes in the nutrition of the 

 fly, rendering the intestine more favourable to the development of the 

 bacteria. In the larva this passage constantly takes place. Larva 

 which develop from eggs laid in sterilised olives, by flies born and bred 

 in a sterile environment, are found to have bacteria in their alimentary 

 canal. 



Action of Tuberculin.* — The observations of A. Calmette and his 

 associates show that the infection of goats and guinea-pigs per os passes 

 to the lungs, and often without leaving any trace of a lesion in the 

 abdomen. The injection of guinea-pigs with tubercle, dried and heated 

 to 100°, causes symptoms identical with those of repeated small doses of 

 tuberculin, whether the animals are already tuberculous or not. 



Tuberculin absorbed by the alimentary canal is toxic for non- 

 tuberculous animals, especially if young. Tolerance is never imparted 

 by increasing doses. Guinea-pigs rendered tuberculous by a single feed 

 (0'02 grm.) always react to tuberculin (1 mg.), a harmless dose to 

 healthy animals. The reaction is obtained equally well by ingestion and 

 by subcutaneous injection. 



Composition of the Tubercle Bacillus.! — - G-. Baudran gives the 

 following analysis of the tubercle bacillus : — 

 Fatty matters — 



Acid-fast Bacilli and Tuberculosis.} — A. Borgeaud has met with 

 two instances of a rare form of tuberculosis which possibly forms a 

 connecting link between the pathogenic and non-pathogenic forms of 

 acid-fast bacilli. The affection presented itself as a hypertrophic 

 enteritis, the wall of the intestine being 4-5 times thicker than normal. 

 There was no ulceration. In the sections of the intestines and adjacent 

 lymphatic glands no giant cells were found ; from a histological point 

 of view there was no evidence of tuberculosis. Yet in the affected parts 

 were myriads of bacilli morphologically and tinctorially identical with 



* Ann. Inst. Pasteur, 1905. See also Comptes Rendus, cxlii. (1906) pp. 441, 616. 



t Comptes Rendus, cxlii. (1906) pp. 657-9. 



J Bull. Soc. Vaudoise Sci. Nat., xli. (1905) pp. 281-7. 



