ROSY APPLE APHIS 
By A. C. Baker and W. F. Turner, 
Entomological Assistants , Deciduous Fruit Insect Investigations , Bureau of Entomology 
CONTENTS 
Page 
Introduction. 321 
Nomenclature of rosy apple aphis. 321 
History and distribution of the species. 325 
Methods of study. 3 2 5 
The egg. 326 
Stem mother. 326 
Spring forms... 328 
Spring wingless viviparous female. 328 
Intermediate form. 330 
Spring migrant. 33 1 
Migrations of the species. 333 
Page 
Summer forms. 335 
Summer wingless viviparous female. 335 
Summer winged viviparous female. 336 
D imorphic reproduction. 337 
Pali forms. 337 
Fall migrant. 337 
Male. 339 
Oviparous female. 339 
Feeding habits. 340 
Summary of life history. 342 
Literature cited. 342 
INTRODUCTION 
The rosy apple aphis is undoubtedly the most injurious leaf-feeding 
apple aphis. Its attacks not only injure the foliage and deform the 
growing apple trees {Mains sylvestris ), but when abundant or unchecked 
it deforms the fruit, causing the production of “aphis apples/’ which are 
unfit for sale. The experiments on which the present paper is based were 
conducted during the seasons of 1914 and 1915 and the manuscript 
prepared for publication during the winter of 1915-16. Besides the work 
recorded in the present paper a study of the embryology was undertaken. 
This work still remains to be completed, the present paper recording the 
life history only after the hatching of the egg. 1 
NOMENCLATURE OF ROSY APPLE APHIS 
The proper scientific name for the rosy apple aphis has for some years 
been in doubt. Pergande, as shown by his manuscript notes, always 
considered it to be Aphis malifoliae Fitch. Other American writers 
usually adopted the view that this name became a synonym of A . soy hi 
Kalt. In studying European specimens and the literature carefully 
the writers have come to the conclusion that A . malifoliae is the only name 
to apply to the species. Their reasons for this view are pointed out under 
the different names following. 
Aphis malifoliae Fitch, 1854.—Fitch (4, p. 760-761; Repr. p. 56-57) 2 
separated our rosy aphis from his mali Fab. in connection with his 
1 During the course of the study the writers were assisted by Miss Dorothy Walton and by Mr. James 
Luckett. Mr. Luckett handled a large number of the experiments during the summer of 1915. 
* Reference is made by number to “Literature cited,” p. 342-343* 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
fa 
(321) 
Vol. VII, No. 7 
Nov. 13, 1916 
K-45 
