GENUS BACTERIUM 279 



described by Loeffler. 7 Kitt 8 has found long filament- forms 

 resembling those of streptothrix. 



Morphology. This organism is present in the heart 

 blood and usually is abundant in the blood vessels of the skin. 

 It is very slender, 1 to 2 ^ or more in length, 0.3 and 0.6 /x in 

 breadth. They sometimes appear as quite long slender fila- 

 ments. They are straight or curved. In the blood they may 

 appear in small clumps. They are often found in considerable 

 numbers in the leucocytes. They do not produce spores. They 

 do not seem to have a capsule. 



Staining. They stain readily with the ordinary aniline 

 dyes. They retain the color when treated by the Gram method. 



Cultivation. The cultivation of this organism is best 

 carried on in nutrient gelatin which gives a distinctly alkaline 

 reaction to litmus paper. 



Agar. At 35 C. on the surface of agar there appear after 

 twenty-four hours round, translucent, convex colonies varying 

 from 0.3 to 0.5 mm. in diameter. In the condensation water 

 a very slight growth takes place. By the third day the 

 colonies, if not crowded, will increase to 1 mm. in diameter; 

 they are round, grayish, with a glistening surface and sharply 

 defined border. A slightly viscid deposit forms in the con- 

 densation water. Within the agar minute grayish colonies are 

 developed. On glycerine agar the growth does not differ ap- 

 preciably from that on the simple agar. 



Gelatin. In needle cultures after twenty-four to thirty- 

 six hours .at the ordinary temperature there develops along the 

 needle track a quite dense, grayish line, due to the crowding 

 together of minute colonies. From the growth along the track 

 of the needle faint, cloudlike processes extend laterally almost 

 to the sides of the tube, giving the gelatin a clouded appear- 

 ance, and to the growth a form resembling that of a "test 

 tube brush." The gelatine is softened, but rarely liquefied. 

 If the reaction is just right, slow liquefaction along the needle 

 track takes place. The colonies, when not crowded, appear in 



7 Loeffler. loc. cit. 



8 Kitt. Centralbl. f. Bakt, Bd. XXII (1897) p. 726. 



