742 Leprosy 



network extended upon the medium. These projections consisted 

 of bundles of the bacilli. 



When a transfer was made from one of these colonies to fresh 

 media, the growth became apparent in a few days and assumed a 

 band-like form, with a plateau-like elevation in the center. 



The bacillus thus isolated grew with moderate rapidity upon 

 all the ordinary culture-media except potato. Upon blood-serum 

 the growth was more luxuriant and fluid than upon the solid media. 

 Upon coagulated serum the growth was somewhat dry and elevated, 

 and was frequently so loosely attached to the surface of the medium 

 as to be readily lifted up by the platinum wire. 



The growth was especially luxuriant upon sheep's blood-serum 

 to which 5 per cent, of glycerin was added. The growth upon the 

 Loffler mixture was also luxuriant. 



Upon agar-agar the growth was more meager; it was more 

 luxuriant upon glycerin agar-agar than upon plain agar-agar, the 

 bacterial mass appearing grayish and flatter than upon blood- 

 serum. The growth never extended to the water of condensation 

 to form a floating layer. 



The bacillus developed well upon gelatin after it had grown arti- 

 ficially for a number of generations and become accustomed to a 

 saprophytic existence. Upon the surface of gelatin the growth was 

 in general, similar to that upon agar-agar. In puncture cultures 

 most of the growth occurred upon the surface to form a whitish, 

 grayish, or yellowish wrinkled layer. Below the surface of the 

 gelatin the growth occurred as a thick, granular column. The 

 medium was not liquefied. 



In bouillon, growth occurred only at the bottom of the tube in the 

 form of a powdery sediment. 



Spronck* believed that he had successfully cultivated the organ- 

 ism upon glycerinized, neutralized potatoes, first seeing the growth 

 after the lapse of ten days. Cultures thus prepared were found to 

 be agglutinated by the blood-serum of lepra cases, and he recom- 

 mended the agglutination test for the diagnosis of obscure cases of 

 the disease. 



Ducrey claimed to have cultivated the lepra bacillus in grape- 

 sugar, agar, and in bouillon in vacuo. His results need confirmation. 



Rostf claimed to have isolated and cultivated the lepra bacillus 

 upon media free from sodium chlorid. The technic of his method 

 is thus described by Rudolph :f 



" Small lumps of pumice stone are washed and then dried in the sun, and then 

 allowed to absorb a mixture of i ounce of meat-extract and 2 ounces of water. 

 This pumice stone is then placed in wide-mouthed bottles and placed in the auto- 

 clave. Each bottle is provided with a stopper through which pass two tubes, the 



* "Weekblad van het Nederlandsch Tijdschrift voor geneeskunde," Deel il, 

 1898, No. 14; abstract "Centralbl. f. Bakt.," etc., 1899, xxv, p. 257. 

 t "Brit. Med. Jour.," Feb. 22, 1905, and "Indian Med. Gazette," 1905. 

 I "Medicine," March, 1905, p. 175. 



