794 FIFTH EEPORT 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°^™ (.05 inch). The general color is reddish 

 brown, differing in intensity wich the stage of development. The sur- 

 face of each egg is marked with numerous delicate carinae, 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 larvae 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 entrance 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 



