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CC. — Reddish, woolly-bordered bark-lice on under surface of 

 elm leaves. 



Elm Bark-Louse. (Gossyparia spuria) 

 CCC. — Cottony masses attached to brown scales on under side 

 of twigs of soft maple, elms, etc. 

 Cottony Maple Scale. (Pulvinaria vitis) 

 CCCC. — Hemispherical reddish scales mottled with black lines 

 on under side of branches of maples. 

 Terrapin Scale. (Lecanium nigrofasciatum) 



II. — Insects Injurious to Greenhouse Plants. 



(a). — Minute, active, white, four- winged flies living on the under side 

 of leaves, sucking the juices; young are oval flat and greenish. 

 White Fly. (Aleyrodes vaporariorum) 

 Control. — Fumigation with hydrocyanic acid gas; spraying with 

 whale oil soap (13^ ounces to 1 gal. water) or kerosene emulsion solution, 

 or Black Leaf 40 and soap. 



(b). — Small, soft, mealy-covered bugs, with eggs enclosed in cottony 

 sacks. 



Mealy Bugs. (Pseudococcus spp) 

 Control. — Wash plants with soap or tobacco solution. 

 (c). — Oval, fiat or saddle-shaped scales, on leaves of lemons, ferns, 

 oleanders, crotons, etc. 



Soft Scale. (Lecanium hemisphericum) 

 (d). — Round scales on leaves and twigs of ivy, date palms, etc. 



Hard Scale. (Aspidiotus spp) 

 Control. — Washing the plants with soap or Black Leaf 40 and soap 

 solution. 



(e). — Green plant lice, often infesting violets and sucking the juices 

 from the leaves, checking the growth. 



Green Aphis. (Myzus persicae) 

 (f). Black plant lice sucking the juices of chrysanthemum. 



Black Aphis. (Nectarophora chrysanthemicolens) 

 Control. — Spray with Black Leaf 40 or Kerosene emulsion. 

 (g). — Red mites, spinning fine webs on under surface of leaves and 

 sucking the juices rendering the leaves sickly yellow\ 



Red Spider. (Tetranychus bimaculatus) 

 Control. — Spraying the plants with clear water or soap solution two 

 or three times a week. 



