168 



CLASSIFICATION OF THE MICRO-ORGANISMS. 



isolated punctiform colonies (provided that the quantity 

 inoculated was minimal) ; or a thin confluent layer 

 is formed along the course of the puncture, so that 

 the line of puncture appears as a thread, while a 

 delicate layer spreads out at its upper end towards 

 the periphery of the jelly (fig 41, b) ; or a thick opaque 

 mass is formed,, filling the channel completely and 



Fig. 41. Puncture cultivations in gelatine. 



forming a markedly prominent kiioh at the orifice 

 of the puncture (figs. 40, a, and 41, a) ; or liquefaction 

 occurs, beginning slowly at the top and confined to 

 the vicinity of the puncture, or energetically and 

 from the first occupying the whole area of the tube 

 (fig. 41, c). At times a turbidity spreads through 

 the gelatine, starting from the line of puncture, which 

 however is not very distinct ; in some cases the jelly 

 appears smoky, or cloudy, in others the growth is 

 more in the form of rays, or of a network of threads 

 Charactcris- (fig. 40, I, c). Where the stroke method is employed 

 stroke culti- we see whether separate little drops form, whether 

 rations on these are glassy and transparent, or white and opaque ; 

 further, whether the growth remains limited to the 



gelatine. 



