December, '09] JOURNAL OF ECONOMIC ENTOMOLOGY • 387 



little larger in the middle and tapering to a rounded distal end 

 entirely without flange, and the two longitudinal rows of conspicuous 

 black spots upon the dorsum are striking characters of this large 

 louse. It seems not to occur in Colorado. See figures 6 and 7. 



Melanoxantherium salicis Linn. This species was taken by Mr. 

 Bragg at "Webster and Springfield, where it was feeding upon the 

 bark of wdllows. Both alate and apterous viviparjB were in the lots 

 taken. The only record we have for this species in Colorado is upon 

 a few specimens taken by Mr. Bragg at Colorado Springs from willow. 

 In general appearance this louse would be readily mistaken for 

 smithice Monell. For characters of antenna and cornicles of alate 

 viviparae see figures 8 and 9. 



Melanoxantherium smithue INIonell. This bark feeding louse was 

 taken at Webster and Springfield where it was abundant on willow 

 limbs. This is a very common species in Colorado, where it is always 

 found feeding upon the small limbs. It is separated at once from 

 any of the other species of this genus that I have seen by its very 

 stout cornicles which are swollen in the middle and contracted at 

 both ends. See figures 10, 11 and 12. 



Chaitophorus aceris Linn. This species, so common upon the leaves 

 of the sugar maple in the Central and Eastern states, I have never 

 seen in Colorado. It was taken at Chicago, Lansing, Detroit, Geneva, 

 Albany and Fort Lee. Both alate and apterous viviparse were seen 

 in each locality. See figure 13. 



Chaitophorus negundinis Thos. This species, which is abundant 

 upon boxelder, Rulac negundo, wherever the tree is planted upon 

 both Atlantic and Pacific slopes in Colorado, was taken on this tree 

 at Lansing, Albany, and Webster. Notice the peculiar double sensoria 

 of the hind tibiae of the oviparous female as shown in figure 14. The 

 antenna of the alate viviparous female is shown at figure 15. The 



Explanation of Plate 13. 



1. Phyllaphis fagi, alate, Albany, July 1; 2 and 3, Lachnus agilis, antenna 

 and hind tarsus, Albany, July 1; 4, Lachnus, near agilis, alate, Albany, July 1; 

 5, Lachnus sp., alate, Washington, July 3; 6 and 7, MeJaitoxantherium floc- 

 culosum, alate, Webster, July 16; 8 and 9, Mel salicis, alate, Springfield, July 

 14; 10, 11 and 12, Mel. smithice, antenna of alate viviparae, alate male and 

 cornicle of alate viviparae, Fort Collins, Colo., September 21 ; 13, Chaitophorus 

 aceris, alate, Chicago, June 23; 14 and 15, Ch. negundinis, hind tibia of ovi- 

 parous female. Fort Collins, November 16, antenna, Fort Collins, June 16; 

 16, Chaitophorus sp., alate viviparae, Portland, Ore., August 22; 17, Ch. vimin- 

 alis, alate, Georgetown, July 5; 18, Ch. populicola, alate, June 26; 19, Chaito- 

 phorus sp., apterous, Geneva, June 29. All figures enlarged 60 diameters. 

 Original. Miriam A. Palmer, Delineator. 



