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tent should be planted to corn the following year; and it will likewise 
be prudent to avoid continuing in corn any field in which the grass- 
green beetle of this species is seen to be abundant in September and Oc- 
aod tober. 
The only other preventive measure worthy of mention is one 
equally to be commended as a general agricultural practice; namely, 
the maintenance of the fertility of the soil by the use of manures, etc. 
This will not, so far as known, diminish in any way the amount of 
insect attack, but it will enable the plant to stand a minor injury with 
| relatively little loss. It is possible that experiments with various kinds 
of fertilizers will show that some of them, the potash salts for instance, 
may have an immediate deleterious effect upon the larve in the earth, 
but we have at present only a speculative basis for this supposition. 
DESCRIPTION. 
Larva (Plate XIV., Fig. 7; and Plate XV., Fig. 2-8).—The corn 
root worm, when fully grown, just previous to its last moult, is .4 of 
an inch in length by one tenth that width, white and smooth when un- 
der a low power, but when more highly magnified, the skin is seen to 
be minutely roughened with very small tubercles. The body is cylin- 
drical, narrowing a little anteriorly, the first segment being the short- 
est and narrowest of all. There are a few scattered stiff hairs to each 
segment, most numerous anteriorly, and especially upon the head. The 
latter is narrower than the first segment, convex but flattened above, 
about two thirds as wide as long, and smooth except for the hairs al- 
ready mentioned. It is yellowish brown, a little darker in front and at 
the sides beneath. A narrow dark lne extends along the middle of 
the head, widest posteriorly, where it is divided by the very narrow 
white suture, which forks at the middle, sending two narrow straight 
branches to the anterior angles of the head. 
Here the short, white, three-jointed antenne are situated, the first 
joint about twice as wide as the last, and the second joint very short. 
The eyes are wanting. The mandibles are dark, with black tips, and the 
other mouth appendages are white. The thoracic segments all bear 
short two-jointed legs, each about as long as the segment to which it 
is attached. They are pale brown, armed with short, stout spines and 
terminating in a single claw and a flattened, membranous, oval ap- 
pendage, which extends some distance beyond the tip of the claw. The 
top of the first segment is coriaceous and yellowish brown while all the 
others are soft except the last, upon which is a circular brownish patch 
of leathery consistence. Beneath this segment is a prominent retractile 
| wart or tubercle, serving as a false leg. The segment is entire and 
3 rounded posteriorly, where it is set with a few long hairs or slender 
spines. 
: Just before pupating, the larva becomes very much shortened and 
thickened, assuming more the form of a common grub. The abdominal 
segments now become much more distinctly marked, and the head takes 
a vertical position. The length in this, which may be called the semi- 
pupa stage, is only about one fifth of an inch, and the greatest breadth 
045 of an inch. The body now tapers more posteriorly than before, 
ine | Me aie Ds 
