408 APHIDS OF THE ROCKY MOUNTAIN REGION 
G.—Cornicle same length as IV, without reticulation; sen- 
soria 18 to 28 on III in alata, 1 to 2 in aptera; unguis not 
longer than III; rostral IV+V .10, not longer than two- 
thirds of base of VI or of hind tarsal II. (p. 302).................... 
Boot et aa at eter The Rose-grass Aphid (Macrosiphum dirhodum ) 
GG.—Cornicle longer than IV, reticulated at tip as far as 
length of hind tarsal II; sensoria 10 to 18 on III of alata, 
2 to 6 in aptera; unguis longer than III; rostral IV+V .15, 
longer than two-thirds of base of VI or of hind tarsal II. 
(ps e324) eee: The Potato Aphid (Macrosiphum solanifolii) 
DD.—Frontal tubercles converging; sensoria present on IV in alata. 
twigs. 
ey cylindrical; sensoria 50-54 on III, 33 to 40 on IV, 8 to 14 on V; capitate 
hairs sparse on body; cornicle in alata same length as III, longer in aptera. (p. 251) 
FADER E ce a Se ea oe A BI oh eee EE a RENE The Oleaster-thistle Aphid (Capitophorus braggii) 
AA.—Cornicle clavate; sensoria on III of alata fewer than 50, on IV fewer than 20. 
B.—Capitate hairs evident and numerous on all body segments in aptera; cauda 
tapering to blunt tip, bearing 2 hairs on each side; sensoria absent on V in alata; 
rostral IV+V with needlelike tip .04 long. (p. 270)................ Capitophorus shepherdiae 
BB.—Capitate hairs evident on only anterior and posterior segments of aptera; 
cauda tapering to acute tip, bearing 4 hairs.on each side; sensoria present on V 
in alata; rostral IV+V without noticeable needlelike tip. (p. 259)........2...--..---.::---- 
pS ek eS ONE 2 ree Pee 2 ee SS eee ee eee Capitophorus hippophaes 
Rye—see Grain Crops 
Snowberry—see Wolfberry 
Spiraea (Spiraea sp.). On leaves and twigs. 
A.—Body light green; unguis about same length as III; cornicle .12 to .30, longer 
than; hindetarsa lel doa( pew li7.9) eerste eens eee The Green Spiraea Aphid (Aphis spiraecola) 
AA.—Body brown; unguis shorter than III; cornicle .10 to .15, about same length as 
hind tarsalee Lon (pet79 eee eee eee The Brown Spiraea Aphid (Aphis spiraephila) 
Spruce, Blue (Picea pungens), engelmann (P. engelmanni) and Nor- 
way (P. excelsa). On bark of twigs. 
A.—Cornicle a mere ring; sensoria oval-transverse; hairs inconspicuous; stigma ex- 
tending to apex of wing; body pale yellow or green, alata with dusky dorsal dashes; 
cauda slightly produced, bearing one pair of apical hairs. (p. 346)........2200.......-esceeeeeeeeeee 
Pe Hei: Rope ieee Me eee ee Seat See as The Balsam Twig Aphid (Mindarus abietinus) 
AA.—Cornicle mammiform, bearing hairs; sensoria circular; hairs more or less con- 
spicuous; stigma of fore wing not attaining apex. 
B.—Tibial hairs short, not longer than diameter of tibia in aptera. 
C.—Body black, with littlé or no pulverulence; legs dark; tibial hairs blunt, 
drooping, numerous, .03 to .05, as long as third diameter of hind tibia in 
aptera, half in alata; rostral IV .23 to .25, shorter than hind tarsal II. (p. 27) 
eNOS BOG SST ae ene eee The Black Polished Spruce Aphid (Cinara coloradensis ) 
CC.—Body bluish black, without pulverulence; legs yellow; tibial hairs 
pointed, semierect, .08 long, slightly longer than diameter of tibia in aptera, 
1.5 times in alata; rostral IV .27, about the same length as hind tarsal II. 
On Engelmann: Spruces (Gps 32)) ice see seecteeer en etcetera ee ete 
SR Were fe oe: Bee DAN Leseseceeeeeerseeeeeees LHe Yellow-legged Spruce Aphid (Cinara hottes1) 
BB.—tTibial hairs long, in aptera once but not more than twice diameter of tibia. 
C.—Tibial hairs at angle not exceeding 60 degrees; body dark brown with 
pattern of pulverulence. (p. 38)........ The Spotted Spruce Aphid (Cinara palmerae) 
CC.—Tibial hairs at angle exceeding 60. 
D.—Hind tarsal II coequal with ITI. 
E.—Dark brown; without powder; rostral IV .20; hind tarsal II .38 
to .49; hind tibia dark. On Norway spruce} (p. 39)-.....2........4s.c-seseeeeeee= 
Saez LO, Oe ee The Dark Brown Spruce Aphid (Cinara piceicola) 
EE.—Body light cinnamon-brown to tan with two rows of green to black 
spots; pulverulence only on intersegmental lines; rostral IV .15; 
hind tarsal II .30 to .35; hind tibia pale. On Engelmann spruce. 
(pit29) eee The Light Brown Spruce Aphid (Cinara engelmanniensis ) 
