The larva mines the underside of oak leaves, forming a tentiform mine, of which the loosened epidermis is slightly wrinkled at maturity.
en.wikipedia.org This slate is usually wrinkled, rich in carbonaceous matter, and scattered throughout are stringers and films of calcite, often carrying particles of pyrite.
en.wikipedia.org Dressed in a wrinkled, long-sleeved button-down shirt, he is baby-faced, and at 18 years old, just barely a man.
fusion.net The leaves are cordiform-emarinate, flabby, dull, limb finely wrinkled (like crepe) between the sub-veins.
en.wikipedia.org The loosened epidermis becomes much wrinkled in the later stages, and the mine is distinctly visible on the upper surface as a tubercular swelling.
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