366 



METHODS USED IN SYSTEMATIC BACTERIOLOOY 



Growth in Blood Agar. 



Colonies. — Description of surface colonies. 



HcBmolysis. — Present or absent ; if present, of a- or ^-type. 



K 



rt 



^^— ^ 



X. 







^dv-if^^ 







m 



m^ ^^^ 



y 



Fig. 57. 



a~g. Elevation of colonies, a. Flat or effuse, b. Raised, c. Low convex, d. Convex or 

 dome-shaped, e. Raised with concave bevelled edge. /. Umbonate. g. Convex with 

 papillate surface, h-o. Edge of colonies, h. Entire, i. Undulate, j. Lobate. k. Cre- 

 nated. I. Erose or dentate, w. Radially striated periphery with lobate edge. 7i. Fim- 

 briate, o. Rhizoid or arborescent, p-s. Growth on agar stroke culture, p. Filiform. 

 q. Slightly spreading with undulate edge. r. Slightly spreading with erose edge. 

 s. Spreading, t-y. Growth in gelatin stab culture, t. Filiform growth without liquefac- 

 tion, u. Crateriform liquefaction, v. Saccate liquefaction, w. Infundibuliform liquefac- 

 tion. X. Stratiform liquefaction, y. Napiform liquefaction. 



Resistance.— Tested usually by placing a 24-hours' broth culture, containing 5 ml. 

 of medium in a f-incli test tube, in a water-bath at such temperatures as 

 55° C. for 1 hour, 60° C. for half an hour, and 80° C. for ten minutes, and sub- 



