THE POTATO TUBER MOTH. 15 
In the files of the Bureau of Entomology there are also records of 
this species boring into the stems of poka or Cape gooseberry (PJiy- 
salis peruviana) , made by Mr. Jacob Kotinsky in Hawaii. The species 
has also been found mining the leaves of PTiysalis mollis and Solarium 
elaeagnifolium, at Brownsville, Tex., by Messrs. McMillan and Marsh, 
of this bureau. 
The tuber moth is unable to increase rapidly on plants which 
confine its activities to mining the leaves, owing to the abundance 
of its parasitic and predacious enemies. In California, therefore, 
only the potato, tomato (figs. 13, 14), and eggplant (fig. 15) may be 
considered as affording suitable protection to the larvae, and of these, 
the potato only is of primary importance. While adults have been 
reared from tomato and eggplant fruit, no important infestations 
have been noted under field conditions, even where moths were 
abundant and close at hand. 
LIFE HISTORY AND HABITS. 
THE EGG. 
The egg, under outdoor conditions, is deposited early in the spring 
on the underside of the foliage of young potato plants. Sometimes 
the eggs are placed on the stems or petioles of the leaves, but more often 
the body of the leaf is selected. In such cases the eggs are placed 
singly, though two or more may be quite close together. Three is 
the largest number that has been noted on a single leaf in the field. 
In bins, or in stacks of potatoes, oviposition takes place through- 
out the winter, but is most general during the warmer months. 
The eggs are usually deposited in the eye or a rough scar on the potato, 
and when placed in this way are generally grouped, as many as 30 
having been found in one eye. In sprouting potatoes the eggs are 
often placed in circles around the base of the sprout. In this way 
they are protected on all but one side. 
Another favorite place for oviposition is at the point of scab in- 
jury, and the narrow deep cracks caused in this way are very often 
filled with the eggs of the tuber moth. Here also they are pro- 
tected. Where the eggs occur in more or less of a mass, scales from 
the wings and body of the moth are thinly scattered over them. 
This probably is not due to an effort of the moth to hide the eggs, but 
is the result of her moving about during the deposition of the egg 
mass. 
In potato bins eggs are often found on the sacks, in depressions 
on the sprouts, and on debris occurring on or between the potatoes. 
However, very small number^ of eggs are found deposited in such 
places, and they generally occur singly. 
The eggs are usually deposited during the evening, night, or early 
morning, although in cool weather and in darkened bins oviposition 
