PLANT-LICE INJURING THE FOLIAGE 319 
To control, spray with tobacco extract or with kerosene emulsion 
as soon as the le are first seen. 
The Currant Aphis (Myzus ribis Linn.) 
Like most other plant lice this species causes a curling up of the foliage 
infested. Both currants and gooseberries are subject to attack. The 
leaves curl tightly, and their upper 
surfaces show distinct raised areas or 
blisters, between the veins. 
The lice are one twelfth of an inch 
long, mottled greén, and have red 
eyes. The pest passes the winter as 
shining eges, attached to the woody 
parts of the plants. 
Contact sprays, such as tobacco ex- 
tract or kerosene emulsion, will kill 
them, but should be applied before Fis. 490.— Work of the Currant 
Aphis. Original. 
the leaves are badly curled. aie : 
The Grapevine Aphis (\acrosiphum viticola Thos.) 
Dusky, soft-bodied plant lice with greenish legs cluster on the tender 
leaves and young shoots of grapevines. They appear in the early part 
of the season, and usually are not noticed after growth is well established 
Fig. 491.— Work of the Grapevine Fic. 492.— The Grapevine Aphis. 
Aphis. Original. Greatly enlarged. Original. 
