68 THE CANADIAN ENTOMOLOGIST. 



slight longitudinal line either side of the pronotum, dusky to blackish. No 

 other dark markings. Cornicles absent, but in the place of each is a pore 

 with a yellow spot just before it. Between the antennae the vertex has a 

 large flat bilobed tubercle or prominence. At the sides of joints 6 and 7 

 of the abdomen there are, on the ventral surface, upon either side, glands 

 that secrete delicate silvery white wax threads which are used to cover the 

 newly-laid eggs (fig. 13). Cauda knobbed as in Callipterus; anal plate 

 bilobed : beak very short, not reaching 2nd coxae. 

 Egos.—i:^\2\Q 3, fig. 13.) 



The eggs when freshly deposited are a beautiful pale yellowish green, 

 lightly covered with bits of slender wax threads from the abdomen of the 

 female. Dimensions of eggs, .71 by .29 mm. They are deposited upon 

 the free surface of the leaves or in the fold along the mid-vein and near 

 the base. 



Described from a louse and her eggs that have been under ol' 

 tion for two weeks in the laboratory (i2-4-'o7). 



This louse differs from the characters that Buckton lays down for 

 Brachycolus by having the 7th joint of the antenna short, and by having 

 the Cauda knobbed as in Callipterus. 



No alate form or pupae have been seen. 



It gives me pleasure to dedicate this interesting species, the first of 

 this genus described in America, to Dr. E. D. Ball, who first discovered it 

 in 1899 upon the grounds of the Colorado Agricultural College. 



Explanation of Plate 3. 

 Plate. — Rhopalosiphiim poce, n. sp. : i, alate viviparous female; 2, 

 joints 3 and 4 of the antenna of same ; 3, apterous viviparous female. 

 Rhopalosiphum nervaium^ n. sp.: 4, apterous oviparous female ; 5, egg of 

 same; 6, alate male; 7, joints 3 and 4 of antenna of same. Macrosi- 

 phum Sa?iborni, n. sp.: 8, apterous viviparous female; 9, joint 3 of 

 antenna of same. Brachycolus Ballii, n. sp.: 10, apterous viviparous 

 female; 11, antenna of same; 12, apterous oviparous female; 13, egg, 

 and 14, antenna of same. All the lice are enlarged 15 diameters. Origi- 

 nal. M. A. Palmer, Artist. 



