lis PRELIMINARY LIST 



to black. Beak reaching second coxae. Abdomen plump and obtuse, dark dusky green, 

 with a marginal row of dots and otherwise barred and mottled with black on dorsum and 

 pleurum. Honey tubes cylindrical, slightly larger at base than at apex, length 0.20 mm 

 Style conical. Tibiae and upper portion of tarsi white. Younger individuals of a pale 

 reddish brown. Winged viviparous females: Length 3 mm. Length of wing 3.90 mm. 

 Length of antennae about 1 mm., joint III 0.35-0.33 mm., IV 0.15-0.16 mm., V 0.15-0.16 mm., 

 VI 0.13-0.13 mm., VII 0.33-0.37 mm. Head, thorax, and greater part of appendages 

 brownish black. Third joint of antennae with an irregular row of about ten sensoria, 

 fourth joint with fewer sensoria. Lateral tubercles of prothorax sometimes barely 

 apparent. Wings rather broad, second branch of cubital nearer tip of wing than to base 

 of first branch. Abdomen rounded and plump, pale yellowish brown, with small spots of 

 black on dorsum and a row of three larger round black spots on each pleurum. Honey 

 tubes about 0.18 mm. long, cylindrical, broadening at base. Style short conical, acute. 

 Tibiae and upper portion of Ijeak white." 



Hotclikiss, Delta Count}^ July 13th in large colonies on 

 the petioles of horse-radish (Cowen). 



Apbis asclepipdis Fitch. 



Hotchkiss, Delta County, August 1st in small colonies on 

 under side of leaves of Asclepias speciosa (Cowen.) 



Aphis bakeri Cowen n. sp. 



"Winged viviparous female: Length 1.80 mm., to tip of wings 3.30 mm. Antennae with 

 all the joints annulated, third and fourth joints strongly tuberculate and with numerous 

 sensoria, joint III 0.37 to 0.33 mm., IV 0.16 mm,, V 0.14 to 0.15 mm.. VI 0.10 mm. A frontal 

 prominence between tlie antennae. Head and tlioraxbhick, venter green, dorsum darker, 

 appendages dark. Venation of wings normal, second branch of cubital midway, stigmatal 

 curved throughout. Honey tubes short, 0.09 mm. long, and 0.045 mm, thick at the some- 

 what swollen lower third. Style 0.08 mm., long, conical. 



Apterous female: Length 1.7 to 3 mm. Some of the smaller individuals are of a rusty 

 color. It resembles Aphis marutea Oestl." 



Fort Collins, June 20th, on stems of Trifolium pratense in 

 large colouies (Cowen). 



Aphis brassicae L. 



Custer County, midalpine, on cabbage (Cockerell, 10). 



Abundant on cabbage wherever cultivated. Specimens 

 fi'om Hotchkiss, Delta County, differ in being lighter in 

 color (Cowen). 

 Aphis cepbalicola Cowen n. sp. 



"Winged viviparous female: Lengthl.70mm., totipof wings3.60mm. Head, antennae, 

 joints of legs, thorax, spots on abdomen, and honey tubes, dark. A large quadrangular 

 gray to green spot on dorsum. Back part of pronotum and most of abdomen yellowish. 

 Tliird joint of antennae tuberculate with numerous irregular sensoria, fourth with few 

 irregular sensoria, all joints strongly imbricated, joints III 0.33 mm., IV 0.14 mm., V 0.13 

 mm., VI 0.11 mm., VII 0.34 mm. Beak hardly reaching second coxae. Thorax arched, 

 lateral tubercle present. Second branch of cubital midway. Honey tubes 0.10 mm. 

 Style about 0.06 mm. Tarsi 0.10 mm." 



Fort Collins, June 30th, usually solitary in heads of 

 Trifolium repens (Cowen). 



