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A A' ECONOMIC ENTOMOLOGY. 



in length, with a black head, a yellow neck, and the rest of the 

 body yellow and black spotted. It has a peculiar habit of hold- 

 ing by the false legs only and dropping the head and anal seg- 

 ments when at rest. The insects feed very rapidly and often 

 defoliate large branches before their presence is realized. When 

 full grown they descend to the ground, burrow a short distance 

 beneath the surface, forming a conical pupa, and remain in that 

 condition during the winter. In spring the moths emerge, and 

 are of a brownish-yellow color, crossed by rather even, narrow, 



Fig. 300. 



The yellow-necked caterpillar, a; its parent, Datana ministra, at b ; eggs, natural size 

 and enlarged, at c and d. 



brown lines ; and this species is Datana ministra. It lays its 

 white eggs to the number of nearly one hundred on the under 

 side of apple and other leaves in a single layer. Similar cater- 

 pillars may be found on a variety of other plants. The sumach 

 is often defoliated, walnut- and oak-trees have their own species, 

 and in all cases the moths have the general appearance already 

 described. Insects that feed thus in company are controlled 

 without difficulty, if we attack them as soon as the colony has 

 hatched. They are then confined to a few leaves, and if these 

 be picked off and destroyed, injury is avoided for the season. If 

 this is not possible, or the colony has already spread too great a 

 distance, then spraying the infested branch with arsenites will 

 answer every purpose. 



There are other caterpillars of this family that attack fruit-trees, 

 but as a rule in such small numbers as to be harmless. 



Oak-trees are occasionally attacked and defoliated by cater- 

 pillars about an inch and a quarter in length, with a yellow head, 



