794 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
leaf above its base, becomes dead and brown, and when opened it is 
found to be entirely eaten out, and to contain, in the proper season, the 
larva or pupa of the above-mentioned insect. 
Fig. 269.— The pine leaf miner, larva, pupa, adult, and work.— After Comstock. 
" What are in all probability the eggs of this insect have been found 
deposited singly near the base of the leaves. They are nearly round, 
flattened on the side of attachment, and slightly so on the opposite side. 
Their average diameter is 1 .4 mm (.05 inch). The general color is reddish 
brown, differing in intensity with the stage of development. The sur- 
face of each egg is marked with numerous delicate carina?, which meet 
at the center, somewhat resembling those of the cotton and boll worms 
figured in the article on cotton insects. We have not proof positive 
that these are the eggs of this leaf miner, but their size, appearance, 
and place of deposit seem to indicate that they are. 
"The work of the growing larva? is well shown in the plate, and also 
the larva itself, highly magnified. From a study of the mines, the larva 
appears to burrow towards the end of the leaf first. Should it arrive 
at the end of the leaf (and it almost invariably does) before attaining 
full growth, it reverses its position and mines towards the base. The 
hole of eutrauce and of future exit is apparently in all cases enlarged 
and the excrement pushed through, as there is but little frass to be dis- 
covered in the mine, while it can always be found in a greater or less 
quantity at the opening or on the leaves below. No instance has been 
observed in which one larva has injured more than a single leaf of P. 
rigida ; but a specimen of this insect was found in Virginia upon the 
common scrub pine (P. inops), the leaves of which are shorter and more 
