NATURAL SCIENCES OF PHILADELPHIA. 321 



ber. It makes a small mine on the under surface, and the leaf is thrown into a fold 

 previously to pupation and the cuticles folded and corrugated. The pupa is 

 contained in an ovoid cocoon within the mine, composed of " frass " and silk. 

 The imago appears in May. The body of the larva is cylindrical. The head is 

 pale brown; the body yellow, with a broad, vascular, reddish brown band. 

 There is doubtless a spring brood, but I have not searched for the larva during 

 the season. 



5. L. basistrigell a. Antenna? silvery. Front silvery, tuft fulvous mixed 

 with silvery. Thorax pale, reddish golden, with a white streak on each side 

 and one in the middle. Fore wings shining ochreous saffron, with a slender, 

 unmargined white basal streak in the fold, a white basal streak along the costa, 

 narrowly dark margined on the extreme costa, extended to the first costal 

 streak, which is silvery white, very oblique and unmargined ; behind this are 

 three small costal streaks of the same hue, the two central dark-margined in- 

 ternally. Opposite the first costal streak is a long, very oblique, silvery white 

 dorsal streak, extended along the inner margin to the base, with dark brown 

 scales between their hinder ends, or exterior to the tip of the dorsal streak, bxit 

 sometimes absent. Nearly opposite the third costal streak is a dorsal silvery 

 streak dark-margined internally. No apical spot, sometimes with dispersed 

 dark brown scales beneath the last costal spot. The hinder marginal line 

 blackish ; cilia pale fulvous. Posterior wings gray, cilia gray with a fulvous 

 hue. 



The larva mines the under side of the leaves of oaks ; I have usually found it 

 in the leaf of the chestnut oak, in September. The mine is limited by two veins 

 of the leaf, and when completed the external epidermis is left transparent. The 

 " frass " is cast on the margins of the mine, and when the larva is prepared to 

 enter the pupa state it collects the grains of " frass " and makes an oval outline 

 of them within the mine, or wall to its cocoon, leaving the cuticles transparent, 

 so that the pupa can be seen within. The imago appears early in May. The 

 body of the larva is cylindrical. It is lemon-yellow along the dorsum, except 

 the three anterior wings, which are whitish, with a series of dark brownish dorsal 

 dashes beginning on the third ring ; on the eighth ring, in some specimens, is a 

 dorsal reddish orange patch. Head whitish, tinged with pale brown. 



6. L. ar g e n t if i m b r ie 1 la. Antenna? silvery, annulated with darkish 

 brown. Head, front and thorax silvery white. Anterior wings silvery, pale 

 golden from nearly the middle to the tip, with a long basal dark brown streak 

 margined above with golden, extending nearly to the first costal streak. There 

 are four silvery costal streaks all dark-margined, the first very oblique, the 

 second convex toward the base of the wing. The first costal dark margin is 

 decided and extended on the costa toward the base. Two silvery dark-margined 

 dorsal streaks, the first opposite the second costal streak. The apical spot 

 black ; hinder-marginal line dark brown, cilia silver gray. Hind wings silver 

 gray, cilia the same. 



Found in the pupa state in the same leaf as the foregoing in the latter part 

 of September. The pupa is suspended within the mine in a very thin silken 

 web. The perfect insect appears early in May. 



7. L. o b s c ur ic o s t e 1 1 a. Head and frontal tuft silvery. Thorax very 

 pale golden. Fore wings pale golden, with a silvery median stripe from the 

 base, black-margined toward the costa, extending to the middle of the wing ; with 

 four silvery costal streaks, the first very oblique and rather long, and all except 

 the last black-margined internally, the margin of the first being long and the 

 continuation of a black streak from the base along the extreme costa. Three, 

 silvery dorsal streaks, the first quite long, obliquely curved and opposite the 

 first costal streak, and the first two black-margined internally ; the second dorsal 

 obliquely opposite the third costal streak. Apical spot black ; hinder-marginal line 

 black, cilia grayish. Hind wings bluish gray, cilia the same. Abdomen black, 

 tipped freely toith yellow. 



1859.] 



