White admiral (northern subspecies) larva of Limenitis arthemis or else a hybrid of southern and northern subspecies. New England is the area where the two subspecies overlap and hybridize. Found on meadow willow Salix petiolaris. Larva mimics bird droppings. Its body is olive green to greenish brown with white areas and a white lateral line. There is a pair of thick, branched horns on top of prothorax and several humps on back (the uplifted end is the rear end).