116 MICROBIOLOGY 



Plumose: a delicate feathery growth. 



Arborescent: branched, or treelike, beset with branched hairlike 



extensions. 

 3. Gelatin stab culture. Liquefying line of puncture. 



Crateriform: a saucer-shaped liquefaction of the gelatin. 



Saccate: shape of an elongated sack, tubular, cylindrical. 



Infundibuliform: shape of a funnel, conical. 



Napiform: shape of a turnip. 



Fusiform: outline of a parsnip, narrow at either end, broadest 



below the surface. 

 Stratiform: liquefaction extending to the walls of the tube anil 



downward horizontally. 



In the examination of cultures on potato, blood serum, 

 egg media, and other solid substances the same observation* 

 should be made. 



Examination of cultures in liquid media. In the study 

 of bouillon cultures it is important to note the appearance of 

 the liquid, whether uniformly, faintly or heavily clouded, 

 turbid, or clear with flocculent masses held in suspension; 

 whether or not there is a surface membrane and if so, its 

 character, whether viscid, friable or flocculent. The reaction 

 of the culture should also be determined. 1 The viscidity of 



Fig. 42. Various forms of watch glasses (crystal, Syracuse and solid.) 



the liquid and especially of the sediment is determined by 

 inserting a platinum loop into it and carefully withdrawing 

 it. If the sediment is viscid, by gently shaking the tube it 

 will rise up, appearing a& a somewhat twisted, tenacious 

 cone with its apex reaching to or near the surface. If fri- 

 able, the sediment will break and become disseminated 

 throughout the liquid. Milk cultures should be examined to 



1 This is accomplished by placing a small piece of each of the 

 red and blue litmus papers in a solid watch glass. With the plati- 

 num loop carefully place a drop of the culture on each piece of paper. 



