70 SHADE TKEES. 



EXPLANATION OF PLATE IV. 



1. 3. The Cottony Maple Scale; Pulvinaria inniimerabilis. 

 la. Pulvinaria acericola; found only on leaves. 



2. The Oyster-shell Scale, Hytilaspis pomorum, natural size. 

 2a. " " female, enlarged. 



2b. " male, enlarged. 



3. Cottony Maple Scale, male, enlarged. 



3a. " one of the recent sets, enlarged. 



4. The Scurfy Scale, Chionaspis fiirfunis, natural size. 

 4a. " female, enlarged. 



4b. " male, enlarged. 



5. Elm leaf with Eggs and Larvae of The Elm-leaf Beetle, Galerucella 



luteola, natural size. 



5a. Elm-leaf Beetle larva, enlarged. 



5b. Adult Elm-leaf Beetle. 



6. San Jose Scale. Aspidiotus perniciosus, enlarged. See Fig. 32. 



