28 
THE SUGAE-BEET WIEEWOEM. 
watered regularly, except on two occasions, during the late summer 
of 1911 and was then allowed to become quite dry. As the larvse 
were killed by the dirying soil they were removed so that they would 
not furnish food for the survivors. On September 12, 1911, the 
cage was again examined and only one larva was found alive. Twp 
dead ones were found near the surface in the dry earth, and they 
had probably been killed by the drying out of the soil. This cage 
was then watered regularly and examined at intervals. The larva 
was stiU alive and active on April 15, 1912. During the latter 
part of April the cage, which was kept m the outdoor insectary, was 
blo^vn over by the wind and broken. Before it was noticed the 
soil had dried out to such an extent that the larva was dead. An 
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3 /^O. 
3 MO. 
3A'^0. 
3 MO. 
3 MO. 
3 MO. 
3 MO. 
3 MO. 
/ 
2 
A „ 
^ 
s 
6 
7 
Fig. 7. — Diagram showing length of life of sugar-beet wireworm without food. (Original.) 
examination of the channels through the cage showed that the wire- 
worm had been quite active up to the time of its death. Wliile 
these larv83 might have secured a little food durmg the earlier part 
of the expermient they could not have done so later, as they were 
checked up and removed when they died. In this experiment 
seven wireworms lived over a year without food, and one almost two 
years,, as shown in the following diagram {^g. 7). 
These wireworms did not grow normally, for when the last one 
died after being in the cage two years it was less than hah size. This 
larva should have pupated that fall, as it was at least a year old when 
the experiment began, and therefore should have been mature. 
