2OO HOMER E. CHENOWETH. 



2. The negative reactions to air of high temperature which gives 

 the same amount of evaporation as dry air is no sharper than in 

 the case of dry air with no difference in temperature (p. 192, 196). 



3. They behaved normally in air of low evaporation, their 

 optimum, but when the evaporation was increased the mouse was 

 stimulated and reacted negatively (p. 192, 194). 



4. Slight differences in air movement were easily detected by 

 the mice (p. 195). 



5. The rate of evaporation is the best index of the combined 

 action of wind, temperature, and dryness of the air. 



6. The integument of animals is important in determining the 

 rate of evaporation, and animals in the same community show 

 differences in their ability to withstand unfavorable conditions. 

 The hair of the mouse makes it nearly as resistant as the heavily 

 chitinized insects. 



7. Evaporation is probably the most important factor in de- 

 termining the distribution of the white-footed wood mouse. 



V. ACKNOWLEDGMENTS AND BIBLIOGRAPHY. 

 This experimental study has been carried on under the direction 

 of Dr. V. E. Shelford, to whom the writer is indebted for constant 

 advise and criticism. To Dr. Adams I wish to express my appre- 

 ciation for his suggestions in the study of the life history. To 

 F. M. Miller is due thanks for his valuable assistance in the con- 

 struction of the apparatus for the measurement of air flow and his 

 suggestions in preparing this manuscript. The equipment was 

 provided by the Graduate School of the University of Illinois. 



Aron, H. 

 'n Investigation on the Action of the Tropical Sun on Man and Mammals. 



Phil. Jour. Sci., B, Med. Sci., Vol. VI., pp. 101-130. 

 Haldane, J. S. 



'05 Influence of High Air Temperatures. Jour. Hyg. (Cambridge), Vol. V., 



pp. 494-513. 

 Hill, Leonard and others. 



'06 Recent Advances in Physiology and Biochemistry. London. Chapters 



VII. to XXI. 

 Kennicott, R. 



's6-'s8 The Quadrupeds of Illinois, Injurious and Beneficial to the Farmer. 



Rep. Comm. Pat., Washington. 

 Hamilton, C. C. 



'17 The Reactions of Some Soil Insects to Evaporating Power of Air, Carbon 

 Dioxide and Ammonia. BIOL. BULL., Vol. XXXII., pp. 159-182. 



