E. M. Doidgk 25 



Sol. N. with agar. On Marshall Ward's Solution N. solidified with 

 agar the organism grew fairly well for the first 24 hours, but did not 

 subsequently extend very much. There was no chromogenesis ; the 

 streak did not exceed 4 mm. in breadth, and was granular round the 

 edges. 



The bacillus grew out into very long threads on this medium, but 

 the filaments did not show the irregularities characteristic of those 

 grown in NaCl solutions. 



Nutrient gelatine (+ 15 Fuller) colonies. When incubated at 20° C, 

 colonies on nutrient gelatine are just visible to the naked eye after 

 24 hours. After 48 hours the superficial circulars are | mm. to f mm. 

 in diameter. They are circular, white and glistening, and the surface 

 being very much raised they have the appearance of small drops of milky 

 water. The submerged colonies are smaller and irregular in outline. 

 All are granular as seen with the microscope under a low magnification. 



In three days the surface colonies have increased still further in 

 size ; they are circular to ellipsoid, and measure up to 1 mm. The 

 smaller colonies are capitate, the larger ones raised ; the margin is 

 wavy and texture coarsely granular; a yellowish tinge is becoming 

 evident, and there is just an indication of liquefaction round the edge 

 of the colonies. The submerged colonies are punctiform to the naked 

 eye; when examined under magnification the majority are spherical, 

 though a few are irregular in outline; they are granular in texture, 

 dense in the centre and thinning out to a pellucid margin. 



The surface colonies can be lifted out entire on the point of a needle. 

 When mounted in water and examined microscopically, the bacteria 

 diffuse very slowly from the compact mass, but those which escape into 

 the water are very active. 



After seven days, the surface colonies measure 1 — 3 mm., and 

 submerged colonies I — § mm. in diameter. The former are very much 

 raised, somewhat moruloid, yellow and with irregular margin ; the 

 shape is also irregular. 



After ten days, each of the surface colonies is sunk in a little saucer 

 of liquefaction, and after 17 days the gelatine is completely liquefied. 

 The yellow colonies are still entire and floating in the liquid medium, 

 though larger and looser in texture than formerly. The colour is 

 similar to, but slightly deeper than, that developed in the agar 

 colonies. 



At 12 — 15° C. similar results were obtained, but growth was decidedly 

 slower. Colonies were not visible to the naked eye until after 48 hours ; 



