iy AN INTRODUCTION TO THE STUDY OF VIRUSES 
Cranberry false blossom 
Sugar-beet curly-top 
Dwarf disease of rice 
Tobacco leaf curl 
Raspberry green and 
yellow mosaics 
Sugar-beet yellows 
Cucumber mosaic 
Sugar-cane mosaic 
Banana bunchy-top 
Strawberry crinkle 
Tulip mosaic or “‘break” 
Potato leaf roll 
Potato Virus Y 
Swollen shoot of cocoa 
Turnip yellow mosaic 
Euscelis striatulus Fall. 
Eutettix tenellus Baker 
Nephotettix apicalis Motsch 
Aleyrodes: Whiteflies 
Bemisia gossypiperda M. and L. 
Aphididae 
Amphorophora rubi Kalt. 
Myzus persicae Sulz. 
Aphis fabae Scop. 
Myzus persicae Sulz. 
Aphis gossipti Glower 
A, fabae Scop. 
Aphis maidis Fitch 
Pentalonia nigronervosa Coq. 
Capitophorus fragaefolii Cockll. 
Macrosiphum gei Koch. 
Myzus persicae Sulz. 
Myzus persicae Sulz. 
M. ornatus Laing 
M. convolvuli 
M. persicae Sulz. 
Aphis rhamni Boyer 
Coccidae Mealybugs 
Pseudococcus citri 
Coleoptera: Flea beetles 
Phyllotreta undulata 
Phyllotreta spp. 
Mustard beetle 
Phaedon cochleariae 
and several other miscella- 
neous biting insects 
Host 
Cranberry 
Sugar beet, beans, toma- 
toes, and many other 
plants 
Rice 
Tobacco and other plants 
Raspberry 
The beet and its varieties, 
including the wild beet 
Cucurbitaceae and many 
other plants 
Sugar cane 
Bananas 
Strawberries 
Tulips and lilies 
Potato and one or two 
other solanaceous 
plants 
Potato and other sola- 
naceous plants 
Cocoa-tree 
Turnips and some other 
members of the Cruci- 
ferae 
Although the list of animal viruses and their arthropod vectors 
shown in Table I is more or less complete, no attempt has been made 
to give all the plant viruses and their insect vectors since it would take 
up a large amount of space and serve no useful purpose. The examples 
chosen, however, include all the types of insect involved and indicate 
the marked preponderance as vectors of sap-sucking insects, , capecially 
the aphides, over the biting insects. 
Miscellaneous Vectors, Intermediate Hosts, and Living 
Reservoirs of Infection 
In the case of the virus of rabies it is necessary for the successful 
transmission by animals that the saliva or other alimentary secretion 
containing the virus should be brought into contact with the nerve 
