6 The Colorado Experiment Station. 
checking their growth and more or less injuring the tree. The de¬ 
tection of their work is no difficult matter a short time after they 
begin feeding, for the leaves of affected twigs soon wilt, as in Fig. 
3, and later dry up from the injury done to them. 
The injury the first brood larvae do to twigs, while sometimes 
alarming, is not usually to be compared with the injury to the fruit 
from the second and third broods. Often this injury to the fruit is 
extensive enough to render great quantities of it unmarketable, and 
we have a condition of peaches comparable to that of apples as a re¬ 
sult of codling moth attack. The larvae usually enter the fruit from 
the stem end and may feed entirely within the flesh, but very often 
they eat their way into the pits. Affected peaches may be detected 
by an issuance of sap mixed with little pellets from the fruit which 
have been chewed up by the larvae. This sap hardens on the out¬ 
side and peaches so effected, are often termed “gummy peaches.” 
The Pupal Stage .—This stage of the insect is said to last from 
6 to 12 days, the first brood remaining pupae for the longest time. 
This period is passed by the first brood pupae, according to Mr. 
Clarke, principally in curls of bark on the trunks of trees. They 
may, however, be found in other places, such as between two 
peaches which come in contact with each other, under rubbish on the 
ground, etc. The cocoon which they make is a very flimsy one; 
in fact, so much so that in reality it should not be termed a cocoon. 
A few strands of silk are spun by the larvae, and to these strands 
the pupae is attached by means of hooks at the tip of the abdo¬ 
men. The second and third brood pupae more often pupate in the 
suture at stem end of peaches than underneath the bark, and the 
semblance to cocoons is even less than in the case of the first brood. 
The Moth .—The twig-borer moth is a tiny, gray insect, about 
inch in length and having a wing expanse of about j/2 inch. It is 
quite a beautiful little moth with its dark gray, fringed wings. They 
are very seldom seen in the orchards by the fruit growers, because of 
their small size, their close resemblance to projections of the 
bark and their habit of resting perfectly still during the day time 
on the trees. 
The Egg .—Eggs of this insect were first found by Dr. Mar- 
latt, who kept the moths in confinement and found that they were 
deposited above the bases of the petioles of the leaves. Mr. Clarke, 
in California, found the eggs of the first brood in the orchard, in the 
same location as described by Marlatt. He found, however, that 
the eggs of the second generation of moths, were laid not on the 
twigs, but on the fruit and in the edge of the stem end depression: 
the eggs of the third generation were found in cracks of the bark, or 
exposed on its surface, just above the crotches formed by the new 
wood, and on the old wood. 
