34 THE SUGAK-BEET WIEEWORM. 
beetles may be found side by side. Now and then, about the middle 
or latter part of April, a beetle is seen sunning itseK at the edge of 
a beet under which it had been hiding. At about this time, also, it 
was noted that the underside of many of the beets which sheltered 
beetles was roughened and had the appearance of being shredded. At 
first no attention was paid to this until by chance a beetle was noted 
feeding on an old beet, and then it was seen that the roughened 
places on the beet were the feeding marks of the adults. TTheneTer 
a beet was turned over the beetles were for the most part active 
(PL XVII, 'G.g. 2), but a few were still in their secondary hibernation 
(PL XVII, fig. 1). The feeding marks on the beets become more 
and more noticeable but are never especially extensive, as the adults 
at the period of then- greatest activity are hght feeders. 
Even at this time the beetles are not entirely normal in their 
actions. This is most noticeable in regard to the habit of feigning 
death, so characteristic of most of the elaterids. ^Vhen a group is 
exposed by removing the beet under which they have been hiding, 
at least haK of them move about seai'ching for shelter. This is 
probably due to the fact that their senses are not very acute at this 
time, and the}^ consider only shelter. About a month later, however, 
when a gToup of beetles is exposed by removing the beet shelter, 
most of them remain quiet for some time, even though they may 
happen to be in an unusual position. 
VARIATION IX THE SIZE OF BEETLES. 
Among the beetles taken in the field there was a very noticeable 
variation in size. (See PL I.) The length was often found to vary 
between 9 and 12.2 mm., and the width between 2.5 and 3.5 mm. 
The larger ones outnumbered the smaller ones ahnost 2 to 1, since 
about 15,000 of those collected could be referred to the larger size 
to about 9,000 of the smaller, while about 2,000 or 3,000 were so 
nearly on the di^^ding fine between the other two sizes that they 
were unclassified. At first the large ones were thought to be females 
and the small ones males, so it was concluded that the females out- 
numbered the males about 2 to 1. Such did not prove to be entirely 
the case, for when copulation became general some of the smaU ones 
proved to be females, and not a few of the larger ones were seen to 
be males. Everything considered, it seems that sex is quite inde- 
pendent of size, for the males and females were seen to occur in about 
equal numbers. 
VARIATION IN THE COLOR OF BEETLES. 
From the outset it was noted that there was great -^^ariation in 
the color of the beetles. This difterence was most noticeable on the 
elytra, which varied from light buff to deep brown or dusky black. 
