REfPOET OP THE ENTOMOLOGIST. 239 



full growth, it reverses its position arsd mines towards the base. The 

 hole of eutrauce aud 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 alv^'ays be found in a greater or less 

 quantity at the opeuiug 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. mops), the leaves of which are shorter and more 

 slender than those of the pitch-pine, and, from observations made upon 

 it, it w^ould seem that one leaf, if small, does not afford all of tlie food 

 needed by a larva. 



When found on the 1st of January this specimen was hibernating, 

 the mouth of its burrow being covered with a thin silken curtain. Six 

 days after, being transferred to a warm room, it was found that this 

 curtain had been broken and the insect had left its mine. It was soon 

 found on another leaf, and the same day formed a new burrow, where it 

 continued to eat until January 23, at which time it had completely ex- 

 cavated the leaf. After this date all operations appear to have been 

 suspended, and there were no signs of life in the burrow until March 3, 

 when a Proctotrupid paraiite issued. 



Leaves of P. rigida are frequently observed to be completely mined 

 out, and nearly full-grown larvae are occasionally found crav/ling about 

 over the leaves and twigs ; so it seems probable that with this species of 

 pine also tw^o leaves may sometimes be successively mined by the same 

 larva. 



The full-grown larva is nearly 5""" in length (.19 inch). Its color is 

 light-brown, with the head and prothoracic shield and the anal plate 

 black. The body is clothed with a few delicate hairs. The form of the 

 larva is shown in the plate. Upon reaching full growth the larva spins 

 a slight covering to the mouth of the mine and retreats a short distance 

 above it (from lO'""' to 15"""). There, after spinning a few supporting 

 lines of silk, it transforms to a long and slender chrysahs, light-brown 

 at tirst but afterwards nearly black. When removed from the mine the 

 pupa is very active, jerking the short end of the abdomen (which extends 

 below the v/ing cases) fi'om side to side with rapidity. The duration of 

 the pupa state is from ten to fourteen days. The moth makes its 

 exit from the pupa shell without disturbing the position of the latter, 

 leaving it attached by its threads some distance up the mine, and works 

 its own way to the entrance. 



There are certainly two broods of this insect each year, probably three, 

 and possibly more in exceptional seasons. Of the general hibernating 

 habits of the genus Stainton says: "Of a few species the young larvae 

 live through the winter, but I believe the greater number pass the win- 

 ter in the egg and pupa state." With the present species the nearly 

 f{d] -grown larvae have been found during the winter, but not in great 

 numbers. What we consider to be the eggs of this species have also 

 been found in apparently healthy condition in midwinter, and the in- 

 sect, without much doubt, hibernates in both of these forms, and possi- 

 bly in either of the others. The moths of the first brood issue during 

 the entire month of June, the difference between the earlier and later 

 ones probably depending upon the form in which they hibernate. 



As we have stated beioi'e, larvae almost identical in appearance with 

 those found on Pi mis rigida in New York have been discovered on the 

 scrub-pines (P. ino]y>i) around Washington. These larvae were bred to 

 the perfect state and proved to bo the same species. 



A leaf miner of precisely the same habits and of almost the same ap- 



