CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 151 



Aphis bakeri on apple and hawthorn = Aphis bakeri on clover. 

 Aphis brevis on apple and hawthorn = Aphis brevis on clover. 

 Aphis euonymi on snowball and burning = Aphis rumicis on bean and dahlia. 



bush 

 Macrosiphum illinoiensis on Viburnum = M. illinoiensis on grape. 



prunifoliae 

 Macrosiphum solanifolii on rose = M. solanifolii on potato. 



Macrosiphum granarium on grains, rose, = M. granarium on cat-tail. 



etc. 

 Aphis prunorum Dob. on plum, Ribes = Rhopalosiphum nymphaeas on Nym- 



phaea, Alisma, Sagittaria, Typha. 

 Rhopalosiphum ribis on Ribes = R. lactucae on Sonchus. 



Rhopalosiphum capreae on willow = R. capreae on Umbelliferae. 



Myzus ribis on Ribes = M. galeopsidis on Galeopsis, Stachys 



and Leonurus. 

 Myzus cerasi on cherry = M. cerasi on Lepidium. 



Myzus persicas on peach = Rhopalosiphum dianthi on garden 



plants. 

 Rhopalosiphum pastinaceae on Lonicera = R. pastinaceae on Pastinaca. 

 Hormaphis hamamelidis Fitch on witch = Hormaphis hamamelidis on birch. 



hazel 

 Hamamehstes spinosus Shimer on witch = Hamamelistes spinosus Shimer on birch. 



hazel 

 Tetraneura graminis on Ulmus = T. graminis on Leersia. 



Thecabius populiconduplifolius on = T. caHfornicus on Ranunculus. 



poplar 

 Chermes floccus on white pine = Chermes floccus on Red and Black 



spruce. 

 Chermes cooleyi on Blue and Engelmann = Chermes cooleyi on Douglas fir. 



spruces 



Aleyrodid^ (White Flies) 



White Fly (Aleyrodes vaporariorum. Westw.). — (Consult Bull. 140, 

 Conn. Agr. Exp. Stn.) Injurious both in adult and nymph stages 

 sucking the juices from the under surfaces of the leaves. 



Often abundant in greenhouses, and difficult to control. 



Adult. — Wings pure white, covered with minute particles of wax; 

 body yellow, Ke inch long; antennae 6-jointed; beak 3-jointed; tarsus 

 2-jointed; eyes brown, in two pairs. 



^Sg^- — Elongate-oval, ^-foo inch long, laid on the leaves; light 

 green or white to dark; hatch in 1 1-14 days. Unfertihzed eggs produce 

 males only; each female usually lays several dozen eggs. 



