374 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 
Aletias, there has not been a single Heliothis. In a warm fall the moths 
have been known to issue during the month of November; but whether 
these individuals die or exceptionally hibernate is as yet an undecided 
point. Our former statement (Third Missouri Entomological Report, p. 
107* ) as to the hibernation of moths was made after observations dur- 
ing a late fall, when most of our specimens issued before winter, and we 
erroneously took this exceptional occurrence for the rule. 
SUMMARY OF THE DISTINGUISHING POINTS COMPARED WITH ALETIA. 
The most salient points of difference between the Cotton Worm and 
the Boll Worm — those which will enable the planter to most readily 
distinguish between the two insects at any stage of growth — may be 
briefly summed up as follows : 
Egg. — The egg of the Aletia is of a delicate bluish-green color, while 
that of the Heliothis is dirty white. Although the two eggs are of 
about the same transverse diameter, the Aletia egg is very flat, while 
that of Heliothis is conical, its longitudinal being equal to the transverse 
diameter. Dr. Phares has neatly expressed the difference in shape by 
likening the egg of Heliothis to an inverted tea-cup, and that of Aletia 
to an inverted saucer. 
Larva. — The full-grown Boll Worm is somewhat longer and much 
thicker than the full-grown Cotton Worm. It early loses the looping 
method of locomotion, which to a certain extent persists throughout 
life with Aletia. The reason for this is that the front pair of prolegs 
(on the third abdominal joint) is well developed in Heliothis, while, as 
we have already seen, it is atrophied in Aletia. The differences in 
the normal markings are well shown upon the plates, yet certain of the 
young Boll Worms so closely, resemble Cotton Worms that some other 
distinguishing character than that of stripes is needed. This character 
is to be found in the piliferous tubercles on the back of both larvre. Of 
these, in each species, there are four upon the upper side of each ab- 
dominal joint. In Aletia these four spots form the corners of a rec- 
tangle. In Heliothis, however, the posterior two are more widely sepa- 
rated than the anterior pair, so that the four form a sort of trapezoid. 
This character is absolutely constant. 
Pupa — The pupa of Heliothis is always found beneath the surface of 
the ground ; that of Aletia is always above ground and usually inclosed 
in a nest of silk and enveloped in a leaf. The pupa of Aletia is slender, 
usually dark brown or almost black in color, and has a dull appearance. 
The pupa of Heliothis, on the other hand, is stout, light brown in color, 
and is smooth and shining. The abdomen of the pupa of Aletia, as has 
already been shown, is elongated and bears on its tip six delicate ex- 
# Most of the mollis issue in the fall and hibernate as such, hut some of them pass 
the winter in the chrysalis state, and do not issue till the following spring. I have 
known them i<> issne in iliis latitude (38^° north) after the 1st of Novemher, when uo 
frost had previously occurred. 
