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ENTOMOLOGICAL SOCIETY. 



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11. Large silken cocoons, 3 inches long tirmly attached to twigs during winter, 

 Cecropia Moth. (Saniia cecropia), Fig. 90. 



Fig. 90. Cocoon of the Cecropia moth. 



12. Elongated white, ribbed cocoons, A inch long, on twigs during winter, — 



Apple Leaf Bucculatrix. (B. pomifoliella). 



13. Mussel-shaped scales with whitish eggs underneath in winter, — 



Oyster Shell BarJc-Louse. (Mytilaspis pomorum). 



14. Whitish scales with purple eggs underneath in winter, — 



Scurfy Bark-Lonse. (Chionaspis furfurus). 



15. Minute black circular scales with a depressed ring about a central nipple, — 



San Jose scale. (Aspidiotus perniciosua). 



16. A mass of eggs on a cocoon fastened to a dead leaf or a twig in winter, — 



Tussock Moth. (Orgyia leucostigma). 



17. Eggs in oval slits, — 



Buffalo Tree- Hopper, (Ceresa bubalus). 



A Key to Plum Insects. 



A. Attacking the Boots : 



1. Burrowing about the crown of the roots, occasionally in young trees, — ' 

 Peach-tree Borer. (Sannina exitiosa). 



B. Attacking the Trunk, Branches, and Twigs : 



1. Making tunnels in the wood ; saw-dust-like excrement at the mouth of unnels, — 



Flat-headed Borer. (Chrysobothris femorata). 



2. Making tunnels in the bark : 



Fruit Bark Beetle. (Scolytus rugulosus). 



3. Bases of buds perforated, the bark becomes discolored, and the leaves and fruit 



wither, — 

 Pear-Blight Beetle. (Xyleborus pyri). 



4. Fixed to Bark : 



a Fiat, or saddle-shaped, or hemispherical dark brown scales. Large scales 

 after mid -.summer are brittle and contain only a whitish dust or empty 

 egg-shells. Wintering forms are small and flattish, — 

 Plum juecanium. (Lecanium cerasifex). 

 h Ashy gray appearance of bark of badly infested trees ; small gray, or black 

 circular scales, — 

 San Jose scale. (Aspidiotus perniciosus). 

 c Mussel-shaped scales, with whitish eggs underneath in winter, — 

 Oyster-Shell Bark Louse. (Mytilaspis pomorum). 

 d. Bark scurfy with white scales, purplish eggs underneath in winter. 

 Scurfy Bark-Louse (Chionaspis furfurus). 



