'l 



means of a logarithmic curve. At 85° C. the increase of 

 the presentation-time is very rapid in tlu- first Imiir; much 

 less rapid after more hours proliminary vvarming; so tliat 

 after 12 hours the curve (Plate III, fig. 2) becomes hori- 

 zontal. At 38° C. on the contrary the increase during the 

 subséquent hours is nearly the same, even more in the 

 second than in the first 12 hours. Moreover the tigures 

 show too much irregularity as to make it possible to 

 extrapolatc to a time zéro. When trying to do so at 35° C. 

 we arrive at a value nearly half as high as the value 

 calculated with the aid of Van 't Hoffs law. At 37° C. 

 the value obtained by this extrapolation is even négative. 

 Hence we find, that the harmful influence of high 

 températures is indeed a time-function, and that this 

 influence makes itself especially felt at the commencement, 

 Thus extrapolation as usçd by Black m an does not 

 apply to our case. 



Now the question arises, whether on account of thèse 

 results Blackmàn's theory has to be'rejected or not. Is 

 there any reason, why this extrapolation was possible in 

 the case of assimilation (Miss Matthaei) and is not 

 applicable hère? 



We can answer this question when taking into account 

 the fact that the favourable influence of high températures 

 also needs time to make itself felt. Thus this favourable 

 influence, whlch causes a shortening of the presentation-time, 

 is also a function of the time of preliminary warming. 



I consider the values found at 30° C. to be the strongest 

 argument in faveur of this opinion; we found there 

 (cf. the table In § 9) : 



1 hour 2 hours 4 hours 6 hours 12 hours 24 hours. 

 30° C. 3'30'' 2'30" 2'10" l'50" l'40'' 1*40" 



Only after 12 hour's preliminary warming the value is 

 reached which would be cxpected according to van 't 



