75 
Such is apparently not the case, however, as two experiments made 
on corn plants show. Two average young phmts of field corn grow- 
ing in the laboratoiy garden were chosen and watched until maturity, 
with the result shown below: 
Table XXVII. — Effect of hollivorm injury to young corn. 
Experiment 1. 
Experiment 2. 
Date. 
Observation. 
Date. 
Observation. 
May 14 
May 15 
May 19 
May 20 
June 2 
June 11 
June 21 
Placed a one-fourth grown larva in bud 
of corn plant 2^ feet high. 
Larva has eaten from one of the partially 
uncurled leaves in the bud; damage 
slight. 
Bud is now badly damaged. 
Damage is greater, but growth is not im- 
paired. 
Plant now 7^ feet high; shows serious 
damage, but is still healthy. 
Now in tassel and silk; is one of the 
healthiest plants in the garden. 
Is bearing two fine ears. 
May 17 
May 18 
May 19 
May 20 
June 11 
June 21 
Placed three larvse (one-fourth, ohe- 
fourth, and one-half grown) on corn 
plant. 
Some damage down in bud is notice- 
able 
Much injury is now noticeable. 
Damage increased; one larva visible 
in the bud. 
In tassel and silk; quite healthy. 
Is bearing a large, healthy ear. 
In these two cases, at least, the plants, although much disfigured 
when young, were fully up to the average in productivity^ later in 
the season. 
At times the feeding of the larvae in corn buds produces a deformity 
resulting in the failure of the developing leaves to unroll normally, 
but such instances are too rare to have any bearing on the question of 
bollworm injury by this brood. 
The injuiy to tassels (PL VII, fig. 2), which occurs later in the sea- 
son, is of small economic importance also, since the few which may 
be partially destroj^ed must have but small effect on the pollen produc- 
tion of the field. 
DAMAGE TO EARS OF CORN. 
It is in the ears that the real damage and loss occurs, but this injury 
is frequently overestimated. In ears of early sweet corn it is not 
exceptional for the larva to bore directly down the ear, as shown in 
Plate VIII, figure 2. In this case the actual number of grains destroyed 
may be considerable, and the filthy excrement distributed over so large 
a space favors decay and subsequent molding of the ears, thus mak- 
ing the corn unfit for the market or table use. Feeding normally 
about the apical portion of the ear, the part affected scarcely ever 
amounts to more than one-fourth or one-fifth of the ear. But the 
extent to which sweet corn is infested, as compared with field corn, 
makes the loss to this crop proportionally heavy. 
In feeding on the larger and more rapidly hardening ears of field 
corn, injury is usually confined to the silk and apical portion, as shown 
on Plate VIII, figure 1. The exact quantity consumed by each larva 
is not readily determined, since it is quite variable. xVf ter the eggs have 
hatched the silks may furnish the food until the larva is from one- 
