INSECTS AFFECTING PARK AND WOODLAND TREES 



551 



plants named above, though it has also been recorded as feeding on sugar 

 maple, shadbush, mountain ash, thorn, rose, witch hazel, elm, oak, birch, 

 willows and poplars. It is kept in check to a considerable extent by 

 natural enemies, prominent among which may be mentioned the small plant 

 bug, Podisus placidus Uhl. The writer has taken five from a single 

 nest and observed six or seven on the outside of another. 



Bibliography 



1898 Felt, E. P. State Ent. 14th Rep t. N. Y. State Mus. Bui. 23, p. 177-90 



Cherry scallop shell moth 



Hydria undulata Linn. 



Brown, webbed-together leaves occur on wild cherry shoots in July and August. 



This species is rather common and attracts notice because of the curi- 

 ous way in which the cherry leaves are fastened together, edge to edge, 

 with the upper surface inside. The yellow, black-striped caterpillars occur 

 within this cavity. It is seldom abundant enough to cause material injury 

 even to its comparatively worthless food plant. This species has been 

 recorded on willow by Dr Packard, though the larvae presented some 

 differences from the typical form on cherry. 



Description. The full grown caterpillars are about 3/g inch long and 

 have a dark amber head and thoracic shield. The body is a variable yel- 

 low, marked as follows : dorsally there are four approximately equal, some- 

 what broken yellowish white lines inclosing brownish yellow lines, and 

 laterally there is a broad, jet-black stripe nearly continuous across the anal 

 plate, venter yellowish white. True legs dark brown, prolegs yellowish, 

 tipped with fuscous. 



Life history. The larvae attain full growth early in August or Sep- 

 tember, enter the soil and transform to pupae within slight silk-lined 

 cocoons where the winter is passed. The moths appear the following 

 spring and deposit their eggs in an irregular cluster on the lower side near 

 the tip of the branch, as recorded by Messrs Comstock and Slingerland. 



