276 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
As larvae have never been carried entirely through their transforma¬ 
tions under observation neither the exact date of pupation nor the 
length of the pupa stage is known. 
All my notes and all the collection records to which I have access 
show that the beetles make their appearance first about July 1. From 
this time on they slowly increase in number, reach their maximum 
early in August and then gradually disappear. They have been taken 
as late as September 30 in Tennessee and Kentucky. 
In the field the beetles are rather difficult to capture. They are 
always alert and at the least disturbance take wing almost as readily 
and quickly as a fly. When cornered they feign death and drop in¬ 
stantly but take flight after falling a few inches. During the day in 
clear weather they remain usually partly hidden among the leaves and 
in the throat of half grown corn plants, coming out to feed and oviposit 
toward dusk and on cloudy days. 
The percentage of infestation even in neighboring fields varies con¬ 
siderably and may reach practically 100 per cent. The date at which 
the corn tassels emerge seems to be the determining factor, the very 
late planted corn being almost entirely free of larvae. It does not 
seem possible to plant early enough to avoid their attacks for the 
earliest tassels to appear are at once attacked. It is probable that 
many of the beetles emerge before that time and feed sparingly on 
various plants while awaiting their favorite food. 
References in literature to the biology of this species are few and 
unimportant. It was described in 1797. Bruner (1891) lists it among 
insects found attacking sugar beets. Riley (1893) notes that occa¬ 
sionally the beetles feed on green corn kernels. Forbes and Hart (1900) 
report its work on sugar beets as injurious. Hunter and Hinds (1905) 
list it among the insects mistaken for the boll weevil and note that the 
beetles are found in flowers. Pierce (1907) lists it but adds nothing 
new to its biology. The adult is fully described and its distribution 
given in some detail by Blatchley and Leng (1916). It seems very 
strange that it has been overlooked by Forbes and his workers in their 
exhaustive studies of corn insects for it must occur at least in southern 
Illinois. 
The only natural enemy of this species so far observed is a minute 
cecidomyid, the salmon-yellow larvae of which enter the egg punctures, 
feed on the eggs and sometimes perhaps even attack the small grubs. 
These predators have been repeatedly observed in the burrows in 
Tennessee and Mr. P. Luginbill sent me from Columbia, S. C., a par¬ 
tially grown beetle larva very evidently killed by the maggot which was 
still feeding upon it. This one was reared and developed into a deli¬ 
cate midge with banded wings. It has not been determined. 
