40 THE SUGAK-BEET WIREWOEM. 
difference in their actions caused by light was very noticeable when 
cages w^ere removed from the insectary and placed in the sunlight. 
The beetles would fly about at once and before long many pairs 
could be taken in copulation. Wlien the cages were replaced ia the 
insectary activit}" would cease as suddenly as it had begun. 
ABILITY OF THE ADULTS TO WITHSTAND UNFAVORABLE CONDITIONS. 
The adults showed remarkable ability to withstand shocks of 
various kinds, whether occasioned by physical injury or by sudden 
and unfavorable climatic conditions. 
A few cases noted in the field w^ill shov/ their ability to withstand 
physical injury. When beetles were collected in the fields individuals 
were noted on several occasions to have been injured by their pre- 
daceous enemies, Calosoma cancellaturn Esch. and C. semilseve Lee, 
and these were separated from the others so they could be watched. 
Those which had merely lost some of then legs did not seem to be in 
the least inconvenienced. Others which were quite severely injured 
managed to survive as long as most of the other beetles. One, wliich 
had its abdomen so nearly severed near the anterior end that it had 
lost one of its elytra, lived for several da^^s. 
As to their ability to withstand unfavorable weather conditions, 
it may be stated that while over 25,000 beetles were collected from 
the field in a period which exceeded a month, very few were found 
dead. During this period there were sudden and great changes in 
temperature and several severe rainstorms. 
In view of the fact that the beetles seem to be so hardy in the field, 
it is difficult to explain the heavy death rate which w^as noted m all 
the cages about the time of oviposition. It seems that they must 
lose much of their vitality during their later life, so that by the time 
oviposition is about to take place they are comparatively weak. 
METHOD AND TIME OF MATING. 
When once the adults have attahied then- normal activity the}^ 
mate readily during the w^armer hours of mild da3^s. Beetles were 
taken mating as early as March 17, 1912, and as late as April 23, 1912. 
Every pair taken in copulation m the field was taken between 9.30 
a. m. and 3 p. m. No pau's were ever found in copulation if there 
was a strong wind blowing or if the sky was cloudy or the weather 
cold and rough. The mated pairs w^ere generall}^ found near or 
beneath the beets under which they had been hiding and feeding; 
though one pair was found in a crack in the soil, about 2 inches below 
the surface. 
Temperature has a very direct effect on copulation, as was proved 
by tlie laboratory experiments. Battery-jar cages, when taken from 
