30 Farmers’ Bulletin 1294. 
It is known to be very numerous throughout the eastern part of the 
country, and many reports of European corn borer occurrence have 
been due to the presence of the smartweed borer. 
The caterpillars of the smartweed borer are about three-fourths 
of an inch long when full grown, slightly smaller than the corn 
borer, and less robust. They are always slate-colored or gray when 
full grown, and in the living state they bear a very fine, faint line 
of darker color running along the middle of the back, whereas in the 
corn borer this line is decidedly broader and very conspicuous in 
the living borer. Except for these differences, and one or two micro- 
scopic distinctions which are discernible only to an entomologist, 
these two kinds of borers have the same appearance when full grown. 
On hatching from the eggs the small caterpillars of the corn borer 
have black heads, while those of the smartweed borer have pale 
amber-colored heads. 
THE CELERY STALKWORM.*, 
In Massachusetts the celery stalkworm has been frequently found 
working in celery stalks along with the European corn borer, and 
on account of its similarity in appearance and damage it has often 
been confused with the latter. The celery stalkworm, however, 
usually confines its injury to the surface of the celery stalks, while 
the corn borer enters the stalks and feeds within as well as upon the 
surface of the stalks. 
The caterpillar of the celery stalkworm is about thirteen-sixteenths 
of an inch long when full grown, and it resembles the corn borer in 
general color. The tubercles, or warts, on its back are larger, darker, 
and support much longer hairs than those of the corn borer. The 
celery stalkworm is much more active than the corn borer, and moves 
backward or forward with equal rapidity. It is not known to 
attack corn. 
THE LINED STALK-BORER.*? 
The lined stalk-borer has frequently been confused with the Euro- 
pean corn borer in Ohio and to a lesser extent in New York. The ~ 
work of the lined stalk-borer greatly resembles that which has been 
described for the stalk-borer, and is usually confined to young corn, 
especially corn which has been planted on sod land. 
The caterpillars of the lined stalk-borer are nearly an inch long 
and yellowish-white, with several conspicuous reddish-brown stripes 
running lengthwise of the body. They may be easily distinguished 
from the corn borer by the presence of these conspicuous stripes and 
by the absence of the small brown tubercles or “warts” which are 
present on the corn borer. 
THE LARGER CORN STALK-BORER.*! 
In the Southern States, and especially in the South Atlantic States, 
the larger corn stalk-borer (Fig. 24) is a common enemy of the corn 
plant, and owing to its habit of tunneling in the stalks of corn it may 
22 Nomophila noctuella Denis and Schiff. * Diatraea zeacolella Dyar. 
33 Hadena fractilinea Grote. 
Se 
