BY R. GREIC4-SMITH. 



387 



quite different from tlie curve pictured by Dean. Tliere is no 

 upward pointing break at the quarter dilution. 



2'he influence of varying thicknesses of the bacterial suspensions. 

 — In this exi)eriinent, the strongest suspension was diluted two- 

 aud four-fold with 0*85 % saline, and the tests were incubated 

 for 10 minutes at 37°. 



Fig. 2. — Varying thicknesses of the bacterial suspensions. 



The experiment brings out several points. There is the 



gradual and uniform rise of the curve in the ease of the thinnest 



suspension of bacteria. This confirms the previous experiment. 



With thicker suspensions, the curves rise more quickly and fall 



