484 REroRT of the Entomologists of the 



The winged females were on the plums in more or less abund- 

 ance during the entire summer. During the latter part of July, 

 August and most of September but few winged females were 

 found and most of these were on the native plums with colonies 

 of young. 



During the early part of September (September 8) the lice were 

 observed to be more abundant in the Station orchard. A few 

 scattering colonies of winged females and young were found on 

 all varieties of plums. These colonies evidently became more 

 numerous toward the middle and latter part of the month. Ovip- 

 arous females were first iobserved about the middle of October, 

 and could occasionally be found on the trees until the first 

 of December. The males were not positively identified. The 

 first winter eggs were found November 11. They were on the 

 twigs, most of them near the winter buds as shown at Plate 

 XXVII, fig. 9. 



Oviparous female. — Body oblong, rounded above and tapering to pos- 

 terior extremity. Size of body 1.33 mm. by 0.5 mm. General color pale 

 green. A medio-dorsal line of darker green extends from the head to 

 about two-thirds the entire length of the abdomen and two faint, green 

 sub-dorsal lines close to the lateral margin, extend the entire length of 

 the abdomen. Antennre six-jointed; length 0.72 mm. (Ill, 0.05 mm.; IV, 

 0.23 mm.; V, 0.05 mm.; VI, 0.22 mm.) Plate XXVII, figs. 7 and 8. 



Winter egg. — Color pale green at first, varying to darker shades. Meas- 

 urements 0.6 mm. by 0.25 mm. Oblong oval in shape, slightly curved and 

 obtusely rounded at the ends. 



Partial hibliograpMcal list: 



1857. Koch, C. L. Die Pflanzenlause — Aphiden, pp. 22-23. Descrip- 

 tions of larva and apterous and winged viviparous females. Figures of 

 apterous and winged viviparous females. 



1877. Bucton, G. B. Monograph of British Aphides, Vol. II, pp. 110-111. 

 Descriptions and figures of apterous and winged viviparous females. 



1892. Herbert Osborne and F. A. Sirrine. Insect Life, Vol. V, p. 23G. 

 Hyalopterus arundinis Fab. (equals pruni Fab.) on plum and choke cherry. 



Other species attaching the plum. — Six or more species are known' 

 to attack the plum. Among those observed by the writer last 

 season are the following: 



Hyalopterus arundinis Fab. This species closely reseml)les the 

 preceding. According to Bucton. it differs in boih size and habits 



