DEATH-SPASM IN PLANTS 103 



former position. If the temperature be raised again, there 

 is once more a growing erection, and when the death- 

 point is reached there is a sudden spasmodic contraction. 



But if the specimen once passes through the tempera- 

 ture at which the spasm takes place, then there should be 

 an abolition of all further response, proving the sudden 

 contraction at 6o° C. to be the spasm of death. Thus, after 

 obtaining the sudden inversion of the curve at 6o° C. in 

 the last experiment, the plant was kept at that temperature 

 for 15 minutes. Cold water was now substituted in the 

 bath, and the record was taken once more of the effect of rise 



Fig. 59. — Abolition of response to warming or cooling in specimen 

 which had passed the death-point. 



and fall of temperature. A record is reproduced (fig. 59) 

 which exhibits the result. In the lower curve is shown the 

 record of effect of rise of temperature from 45 ° to 65 ° C, 

 and in the upper the effect of cooling from 6o° to 45 C. 

 It is seen that while in the last experiment the plant 

 exhibited a spasmodic contraction at 6o° C, there is no 

 trace of such an effect in the present case. The very slight 

 movement observable in the two curves is the physical 

 effect of heating and cooling, quite negligible compared 

 with the physiological erectile movement due to warm- 

 ing and the subsequent spasmodic contractile movement 

 heralding the initiation of death-change. 



