16 APHIDS OF THE ROCKY MOUNTAIN REGION 
where they are pointed and .05 long. First and second pairs of femora somewhat thickened. 
Rostrum obtuse, attaining between 3d coxa and middle of abdomen. 
Ovipara. Apterous. Same color as apterous vivipara except slightly dusky on abdomen 
and appendages. Body 1.40; antenna .35; hind tibia very slightly swollen, bearing sensoria 
along posterior side. Many showing 2 ova inside of body. 
Egg. Black, naked. Size .86 by .33. 
Collections. On Pinus edulis in abundance, rarely on ponderosa var. 
scopulorum and P. flexilis, on needles especially at bases; solitary. Colorado: 
Near Cameron Pass, Owl Canyon (in Larimer County). Utah: Logan Canyon. 
Apterous summer viviparae Aug. 24 to Nov. 8, oviparae Oct. 27 to Nov. 6; 
abundant but difficult to find on account of secluded habitat, solitary habits, 
small size, protective color and agility in escaping. 
Type. U.S.N.M., No. 41952. Paratypes, Colo. Agr. Exp. Sta. and Essig 
Collections. 
Chief Distinguishing Characters. Shortness of the tibial hairs (.01, much 
shorter than diameter of tibia) and absence of dusky spots on dorsum of body. 
Essigella pini Wilson 
The Speckled Pine Needle Aphid 
Hd.Ti- oe fey 
Ss secs cane a 
loess 07-1 09 : ‘ pt. Viv. 
Fig. 10. Essigella pini 
Essigella pini Wilson 1919a:2; Knowlton 1930:158; Gillette and Palmer 1931:841. 
Apterous Summer Vivipara. Pale greenish yellow, with rows of dusky spots on dorsum; 
appendages yellow with dark tips; tarsi blackish. Body 1.5-2 by .45; hind tibia .70-.95; hind 
tarsal II .17-.20; antenna .45-.50. Hairs slightly capitate; on hind tibia, set at angle of 30 
degrees, length equal to diameter of tibia; on vertex same as on tibia. Rostral 1V+V 
.07-.08, attaining abdomen. 
Ovipara. Apterous. Same as apterous vivipara except hind tibia which bears large 
round sensoria along ventral side. 
Collections. On Pinus ponderosa var. scopulorum, rarely P. contorta var. 
murrayana, on bases of needles in tips of twigs. Colorado: Foothills near Fort 
Collins, Bellvue, Gould, Cameron Pass and Poudre Canyon. Utah: Marysvale 
and Logan Canyon. Fundatrix May 24, apterous summer viviparae May 8 to 
Sept. 17, oviparae Aug. 20 to Oct. 13; rare. 
Type. Granovsky Collection. 
Chief Distinguishing Character. The length of the tibial hairs (about same 
length as diameter of tibia). 
Genus Eulachnus Del Guercio 
Del Guercio, 1909:327; Baker, 1920a:15. 
Characters. As given for Eulachnina also as follows: Antenna six-seg- 
mented, primary sensorium proximad to unguis; hairs long, stout spines; fore 
wing with media faint, usually once-branched; claws simple. Living on needles 
of Pinus sp. 
Genotype (fixed by Wilson, 1911b:54), Lachnus agilis Kaltenbach. 
Key to Species of Eulachnus 
1. Body green. On Pinus sylvestris (p, 16)$2.osec un eee agilis 
Body brown. On Pinus ponderosa var. scopulorum and P. palustris (p. 17) -.-....------ rileyi 
[Genotype Eulachnus agilis (Kaltenbach) ] 
Lachnus agilis Kaltenbach, 1843:161. 
Schizolachnus agilis, Mordvilko, 1908:375. 
Eulachnus agilis, van der Goot, 1915:389. 
Alate Vivipara. Head greenish with brown blotches, leaving median line pale; thorax 
