IO2 VICTOR E. SHELFORD. 



Pletkodon cinereus is quickly affected and over-stimulation and 

 coiling appear within one minute while in the dry and rapidly 

 moving air from two to ten minutes are required to bring about 

 the same result. All the activities and symptoms of loss of 

 water are the same as in the dry air (p. 86). In the gradients 

 (Table VI.) one of the graphs shows less clear avoidance of the 

 hot air due to over-stimulation and some loss of correlation in 

 movement. Otherwise the reactions were entirely similar. No 

 temperature experiments were performed with P. glutinosus but 

 the difference in behavior in hot and dry air in the tubes was 

 comparable to that of cinereus. 



Rana behaved exactly as in the dry air in the experiments, 

 with only five degrees increase, but the graph of the gradient 

 experiment with ten degrees difference is like that of Plethodon 

 as a very clear orientation occurred. 



Fontaria showed the greatest difference when compared with 

 the dry air. The activity was much greater in the hot than in 

 the dry or moving air. Movement in the tubes was increased 

 six times with an increase of 8 C. In the gradient a distinct 

 orientation occurred, the animal turned back upon encountering 

 the hot air. This was a decided difference from the reaction 

 to dry and moving air (compare graphs of Chart II., p. 91). 



Some of the toads showed stimulation in the hot air. Activity 

 was increased in the tubes and in the gradient experiments some 

 of the individuals tended, to hop back and forth in the warm end 

 (Chart II., Exp. 76) and only a weak negative reaction resulted. 

 The detailed behavior of Geolycosa was not markedly affected 

 by the difference in temperature and a slightly positive re- 

 action was given. Cicindela lecontei was likewise positive in the 

 gradient (see Table VII.) but in the tubes showed a greater 

 tendency to "clean" the legs and antennae while in the hot air. 



4. Death through Evaporation. 



All of the animals studied may be killed by loss of water. 

 The results are given in Table VII. It will be noted that where 

 records of size were preserved, the smaller animals died from 

 loss of water much more quickly than the larger. This is perhaps 

 due to the fact that the surface is greater in proportion to the 



