3(52 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 1 



bright salmou red in color. The antenna is about two thirds as long as the 

 body, or approximately 1.45 millimeters; length of body 1.70 to 2 mm.; cor- 

 nicles .33 mm. I have not been able to see any sensoria upon 3d joint of an- 

 tenna, but altout 25 small circular sensoria occur upon each hind tibia. See 

 Plate 6, figs. 16 and 17. 



The eggs are deep green when first laid but become shining black in a few 

 days. They are .66 mm. long by .33 mm. broad and are deposited chiefly in 

 the axils of the buds. See Plate 8, fig. 11. 



Male. 



Taken on peach leaves by L. C. Bragg. Ft. Collins, Colo., November 4, 1908. 



Colors practically the same as in spring migrant but with the black or 

 blackish markings, at least in some specimens, more extensive; cornicles 

 dusky to black, moderately swollen, as in fall migrating female. Lengths: 

 Body, 1.85 mm.; wing, 3.20 mm.; cornicles, .34 mm.; antenna, 2.30 mm. 

 Joints: III, .56; IV, .49; V, .40; VI, .14; VII, .60 mm. Numerous small cir- 

 cular, modei'ately tuberculate sensoria upon joints 3, 4 and 5. See Plate 

 6, fig. 15. Frontal tubercles and 1st antennal joints are rather strongly 

 swollen. 



The male is a fall migrant, going to the trees from the summer host plants, 

 and is not the offspring of the female fall migrant. The latter gives birth to 

 the apterous oviparous females only. 



The Black Cherry Louse, Myzus cerasi Fab. ; Plate 8, Figs. 1, 2, 3. 

 Some of the More Important Literature 



Aphis cerasi Fab. Syst. Ent., p. 734, 1822. 



Aphis cerasi Fab. Kaltenbach, Mon. Fam. Pflanzenlause, p. 45, 1843. 



Aphis cerasi Fab. Koch, Die Pflanzenlause, p. 87, 1857. 



Myzus cera-Ki Fab. Buckton, British Aphides, V. I, p. 174, 1876. 



Myzios cernsi Fal>. Fitch, Cat. Homop. N. Y., 1851 (Lintner's 9th Rep. Ent. 

 N. Y., p. 405). 



Myzus cerasi Fab. Thomas, Ent. 111. Sth Rep., p. 75, 1880. 



Myzus cerasi Fab. Oestlund, Apb. of Minn., p. 73, 1887. 



Myzus cerasi Fab. Weed, C. M., Bull O. Expt. Sta. Tech. Ser., V. I, No. 

 2, 1890. 



Myzus cerasi Fab. Theobald. Rep. Econ. Zool., p. 48, 1908. 



This coal black louse is the only aphid of any importance as a pest 

 upon the cultivated cherry in Colorado. It continues upon cherry 

 foliage throughout the season and neither my assistants nor myself 

 have been able to discover it upon any other tree or plant. 



EXPLAXATION OF PLATE 



Plate 8: Figs. 1-3 Myzus cerasi; 1, adult, apterous viviparous female; 2, 

 winged viviparous female; 3, winged male. Figs. 4-11 Myzus persicce; 4, 

 young stem-mother ; 5, adult stem-mother ; 6, recently hatched young of stem- 

 mother ; 7. apterous viviparous females, second generation ; 8, spring migrant ; 

 9, winged viviparous female, fall migrant; 10. oviviparous female; 11, egg. 

 Figs. 12-15 Hippodamia conrcrgens; 12. adult; 13, larva; 14, pupa; 15, cluster 

 of eggs. M. A. Palmer, artist. Original plate in Bui. 133, Colo. Exp. Station. 



