326 



W. J. CROZIER 



time factor enters in two ways, for in addition to the slow exhaus- 

 tion which occurs even at the normal temperature and is itself 

 probably affected by temperature, extreme thermal conditions 

 also exercised a characteristic effect of their own which was mani- 

 fested in a kind of hysteresis. By a condition of hysteresis I 

 mean that subjecting a holothurian or its.isolated cloacal end to 



TABLE 6 



Experiment 33.2. June 21. Stichopus moehii, 31 cms. long; 83 seconds for ten 



pulsations 



TABLE 7 

 Experiment 39.4- JUne 24. Stichopus moehii 29 cms. long; 74 seconds for 10 

 pulsations, at 24-3°. Fifteen minutes after excision, plunged successively into 

 water at different temperatures 



