Dec. 15,1923 
The -Eggplant Leaf-Miner 
569 
PUPA 
The pupa (PL 1, C) is spindle-shaped, being widest across the thorax. The head is 
rounded and the abdomen tapers to the posterior extremity. The surface shows 
numerous minute punctures and small wrinkles. On the head and thorax the punc¬ 
tures are for the most part in impressed lines, while on the abdomen they are more 
evenly distributed. On the dorsal surface of the anal segment there is a short, stout 
elevation that ends in a hook. This segment also bears about 14 spines, with hooked 
ends, arranged in a circle. Small hairs also occur at intervals over the surface of the 
head and abdomen. 
Pupae have been seen, apparently just formed, that were of a deep blue color. More 
mature specimens are dark brown. 
Pupae vary considerably in size, ranging from 3.43 millimeters in length and 1.05 
millimeters in width to 5.19 millimeters in length and 1.76 millimeters in width. 
HABITS 
Moths confined with growing eggplants and provided with sweetened 
water deposited eggs singly on both surfaces of the leaves. They were 
not firmly attached to the leaf surface. 
Chambers (3, v. 5, p. 176) and Murtfeldt (7, p. 244) , besides giving 
a short description of the larva, have also given brief attention to 
its mining habits. So far as observed, the mines in eggplant (PI. 1, D) 
and Solarium carolinense are always along the edge of ttys leaf. A number 
of larvae sometimes work in a single leaf and at least two have been 
found using what were apparently parts of the same mine. The mined 
portion of the leaf has the appearance of a dry, oftentimes puffy, blotch, 
the older mined area being dead and brown. The leaf becomes dis¬ 
torted about the mine and sometimes curls over it, but no silk is ap¬ 
parent on the leaf surface. The larva removes the parenchyma and 
constructs a firm silken tube, in which it is often found, within the mined 
area. 
In its larval habits Phthorimaea glochinella apparently differs from Ph. 
operculella in that it feeds entirely within the leaf, not leaving the mine 
to roll the leaf or feed on other portions of the plant. The fact that the 
mines seem invariably to be made along the edge of the leaf is also a 
habit not shown by operculella, and Morgan and Crumb (< 5 , p. 4) state 
that the larva of operculella shows no tendency to form a firm, cylindrical, 
silk-lined tube. 
When full grown the larva constructs a loose, silken cocoon in which 
to pupate. In rearing cages these have been found just below the surface 
of the soil and among remnants of dead leaves on the soil surface. Obser¬ 
vations made in the field indicate that this is the habit under natural 
conditions. 
The period of incubation of eggs kept in a well-ventilated insectary at 
Baton Rouge during June was about 7 days. On June 21 larvae that 
had just issued were placed on eggplant leaves in the insectary and from 
these moths began to issue on July 15, giving a period of 24 days for the 
combined larval and pupal stages. As larvae have been taken from 
leaves in the field from early May to the middle of November, there 
may be several broods during a year. The winter months are apparently 
passed in the pupa stage. 
NATURAL ENEMIES 
In writing of Phthorimaea operculella , Graf (5, p. 32) states that when 
this species works as a leaf-miner its numerous parasitic enemies do 
much to keep it in check. Parasites apparently play an important part 
