STJPERFAM1LY TINEOIDEA 



123 



this moult they emerge from the mines and going to the 

 tip of one of the lobes turn it back upon the lower surface 

 by attaching it there with silk. They spin a web at the 

 border of this bent-over portion and use it as a shelter 

 within which to feed. They eat away the soft tissue of the 



Fig. 39 FlG - 40 



Fig 39. Leaf of box elder with a mine of Gracilaria negundella in one 

 leaflet, and a cone (rolled up) in another leaflet. 



Fig 40 Diagram of a chestnut leaf with a normal mine of Acrocercops 

 strMnitella (In part after Heinrich and De Gryse ) e, egg and entrance 

 he 2 y 1 andl; the course of the first two sap-feeding larval mstars through 

 the leaf membrane; 3, the course of the third, transition mstar down a 

 lateral vSn?J and 5, the course of the later, tissue-feeding instars in the 

 mid rib, x, exit hole. 



enclosure leaving only a skeleton and the upper cuticle. 

 Before all the tissue is removed from the interior of this 

 shelter— a portion is seemingly retained for protection— the 

 larvae may cause a second bend to occur, turning the end 

 of the lobe about a centimeter farther back. The excre- 



