PLATE XIII. Coccidae, Scale Insects. 



i. Orthezia insignis Douglas, — greenhouse orthezia, x 2.5. 



2. Aster olccanium variolosum Ratzeburg, — pit-making oak scale, 



x 1. 



3. Gossyparia spuria Modeer, — elm scale, x 1. 



4. Kermcs sassceri King, x 2. 



5. Phenacoccus acericola King, — woolly maple leaf scale, males 



on bark, x I. 



6. Phenacoccus acericola King, — females, x 1. 



7. Pseudococcus citri Risso, — common mealy bug, x 1. 



8. Lecanium corni Bouche, — European fruit lecanium, x 1. 



9. Pulvinaria vitis Linnaeus, — cottony maple scale, x I. 



Photographs : 3 and 5 by W. E. Britton ; others by B. H. 

 Walden. 



