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Walsh calls malefica the “culprit leafhopper” and says “occurs on 
apple and pear leaves. Took a pair in coitu under bark, early in the 
spring, in the woods.” In another place he states that this species and 
maligna are supposed to be the cause of fireblight. In the Prairie 
Farmer of the next year (April 4, 1863) he discussed this further in 
connection with eggs found in apple twigs which he identified as the 
eggs of malefica. This species hibernates in the adult stage which agree 
with his finding them under bark in the early spring but would not agree 
with his identification of winter eggs. A study of his description and 
figures of the eggs shows conclusively that they were those of a tree- 
hopper ( Ceresa ) and not of any leafhopper. As this is the only apple- 
infesting species of Empoasca that winters as an adult, there could be 
little question of the correctness of the determination on that ground 
alone, but when taken in connection with Walsh’s accurate comparison 
with maligna , the other apple-infesting species, the identification is 
definite and complete. 
This species is a much more serious pest of potatoes than it is of apples, 
in fact it is not ordinarily an apple pest but only a nursery stock pest. 
Although named fabae, it is only secondarily a bean pest and should un¬ 
doubtedly be called the potato leafhopper. 
Much additional confusion has arisen from the unstable character of 
the white markings of this species. A majority of the mounted material 
shows no markings at all—such examples are usually determined as 
viridescens. Others show three spots on the pronotum and a pale line 
on the scutellum and are often determined as flavescens while the few 
that show the complete spotting have been determined as mail. 
Bibliography 
1889 Woodworth, C. W. North Amer. Typhlocybini. Psyche, Vol. V, pp. 211- 
214. 
1898 Gillette, C. P. Amer. Leaf-Hoppers of the Subfamily Typhlocybinae. Proc. 
U. S. Nat. Mus., Vol. XX, pp. 709-773. 
1909 Parrott, P. J. “Scientific Notes”, Jour. Econ. Ent. Vol. 3, p. 79. 
1918 Childs, Leroy. The Life History and Control of the Rose Leaf-Hopper. 
Oreg. Exp. Sta. Bull. 148. 
1918 Lathrop, Frank H. Leafhoppers Injurious to Apple Trees. Geneva New 
York Exp. Sta. Bull. 451. 
1919 Ball, E. D. The Potato Leafhopper and the Hopperburn that it causes. 
Wis. Dept. Agric. Bull. 23, pp. 76-102. 
1923 Fenton, F. A. and Hartzell, Albert. Bionomics and Control of the Potato 
Leaf-hopper. Ia. Exp. Sta. Research Bull. 78. 
1924 Hartzell, Albert. The Genus Empoasca in North America. Ia. Acad. 
Sci. Vol. 30, pp. 87-133. 
See Gillette, Fenton and Hartzell for further references. 
