456 



NELLIE M. PAYNE. 



polyhedralskrankheit. In this disease both the freezing point 

 and the conductivity of the blood approach that of water. In 

 Fig. 3 the conductivities of the Japanese beetle larval blood are 

 plotted against survival temperature. Cold hardiness in this 

 species is more fully measured by conductivity than by either 

 moisture content or undercooling point. 



-36 / 



-28 



-24 



K! 



-16 



-12 



CD 



-8 



-4 



RELATION BETWEEN UNDER- 

 COOLING AND SURVIVAL 



TEMPERATURES IN 

 DENDROIDE5 CANADEN5IS 



Undercooling point 



Survival temperature 



-4 -8 -12 -14 -20 -24 -28 



UNDERCOOLING POINT 



Fie. 7. Relation between undercooling and survival temperatures in Dendroides 

 canadensis. Undercooling point - ; survival temperature . 



