CLASSIFICATION OF BACTERIA 287 



RAISED, growth thick, with abrupt or terraced edges. 



RHIZOID, growth of an irregular branched or root-like character, as in 

 B. mycoides. 



RING, same as RIM, growth at the upper margin of a liquid culture, adhering 

 more or less closely to the glass. 



REPAND, wrinkled. 



RAPID, developing in 24 to 48 hours. 



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



SCUM, floating islands of bacteria, an interrupted pellicle or bacterial membrane. 



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



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



SPORANGIA, cells containing endospores. 



SPREADING, growth extending much beyond the line of inoculation, i. e., sev- 

 eral millimeters or more. 



STRATIFORM, liquefying to the walls of the tube at the top and then pro- 

 ceeding 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. 



TRUNCATE, flat-ended, instead of tapering, rounded, or concave. 



TURBID, cloudy with flocculent particles; cloudy plus flocculence. 



UMBONATE, having a button-like, raised center. 



UNDULATE, border wavy, with shallow sinuses. 



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



VERMIFORM-CONTOURED, growth like a mass of worms, or intestinal coils. 



VILLOUS, growth beset with hair-like extensions. 



VISCID, growth follows the needle when touched and withdrawn, sediment ore 

 shaking rises as a coherent swirl. 



ZOOGLOEAE, firm, gelatinous masses of bacteria, one of the most typical exam- 

 ples 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. 



ADJUSTMENT OF REACTION OF MEDIA BY TITRATION WITH 

 PHENOLPHTHALEIN. 



Required Apparatus and Solutions. — Two burettes (Fig. 69), 

 (one at least with a rubber tube outlet for the alkali; the other may 

 have a glass cock). A six-inch porcelain exaporating dish, with 

 tripod, wire gauze and stirring rod. A Bunsen burner, cylinder 

 graduate, and 5 c.c. pipette. Normal NaOH solution, normal HCl 



