CLASSIFICATION 43 



SACCATE, liquefaction the shape of an elongated sack, tubular, 

 cylindrical. 



SCUM, floating islands of bacteria, an interrupted pellicle or bac- 

 terial membrane. 



SHORT, applied to time, a few days, a week. 



SLOW, requiring 5 or 6 days or more for development. 



SPORANGIA, cells containing endospores. 



SPREADING, growth extending much beyond the line of inocula- 

 tion, i. e., several millimeters or more. 



STRATIFORM, liquefying to the walls of the tube at the top and 

 then proceeding downwards horizontally. 



THERMAL DEATH-POINT, the degree of heat required to kill 

 young fluid cultures of an organism exposed for 10 minutes 

 (in thin-walled test tubes of a diameter not exceeding 20 mm.) 

 in the thermal water-bath. The water must be kept agitated 

 so that the temperature shall be uniform during the exposure. 



TRANSIENT, a few days. 



TURBID, cloudy with flocculent particles; cloudy plus flocculence. 



UMBONATE, having a button-like, raised center. 



UNDULATE, border wavy, with shallow sinuses. 



VERMIFORM-CONTOURED, growth like a mass of worms, or in- 

 testinal coils. 



VERRUCOSE, growth wart-like, with wart-like prominences. 



VILLOUS, growth beset with hair-like extensions. 



VISCID, growth follows the needle when touched and withdrawn, 

 sediment on shaking rises as a coherent swirl. 



ZOOGLOEAE, firm gelatinous masses of bacteria, one of the most 

 typical examples of which is the Streptococcus mesenterioides 

 of sugar vats (Leuconostoc mesenterioides), the bacterial 

 chains being surrounded by an enormously thickened firm 

 covering, inside of which there may be one or many groups of 

 the bacteria. 



NOTES. 



(1) For decimal system of group numbers see Table 1. This 

 will be found useful as a quick method of showing close relation- 

 ships inside the genus, but is not a sufficient characterization of any 

 organism. 



(2) The morphological characters shall be determined and de- 

 scribed from growths obtained upon at least one solid medium 

 (nutrient agar) and in at least one liquid medium (nutrient broth). 

 Growths at 37 C shall be in general not older than 24 to 48 hours, 

 and growths at 20 C not older than 48 to 72 hours. To secure uni- 

 formity in cultures, in all cases preliminary cultivation shall be 



