SUBORDER JUGATAE 73 



the eggs of a native species, E. auricyanea, are laid singly 

 near the edges of the opening leaves of oak, chestnut or 

 chinquapin in April. In this case dissection of the abdomen 

 shows that the number of eggs laid by a single female is 

 about forty. 



After the eggs of Eriocrania are laid they swell sometimes 

 to more than twice their original size to fill the pocket. 

 After a week to fifteen days the larvae emerge from the egg 

 and begin to mine in the leaf. They are found particularly 

 on species of the birch and oak families, i.e., birch, hazel, 

 oak, chestnut, beech. The mine often begins as a gallery 

 but soon expands to a blotch which may or may not involve 

 the part of the leaf where the gallery was at first. 



According to Busck and Boving this early part of the 

 mine of E. auricyanea is normally obliterated, making a 

 fissure in the growing leaf. Infested leaves may often be 

 located by this fissure. The blotch becomes big and bulgy 

 and is "suggestive of a sawfly or beetle mine." The entire 

 parenchyma is eaten out and the mine is equally visible from 

 both sides and so translucent that one may easily see the 

 larvae and the black frass which is voided in long irregularly 

 curled threads. By these threads of excrement one may 

 almost certainly identify an eriocranid mine even when the 

 miner has departed. 



Larvae. The larvae are apodal. The full-grown larvae 

 of E. auricyanea are 9 to 10 mm. long, whitish in color and 

 somewhat flattened. The head is small. Segments two to 

 four are broad and according to Meyrick have minute 

 "subdorsal and supra-ventral" protrusible papillae. The 

 fifth segment has lateral projections. It then tapers poste- 

 riorly to a very narrow anal segment. 



Concerning behavior while mining, Kearf oot gives a brief 

 account of an eriocranid larva which he found in the leaves 

 of chestnut at Mont Clair, N. J. early in the spring of 1902. 

 In this case history repeated itself in that Kearf oot, like the 



