A SYNOPSIS OF THE APHIDIDAE 105 



I to 4 (av. 3). Lateral abdominal tubercles could be found only on 

 the first and seventh segments. 



Alate viviparous female. Measurements: Body length, 1.768 to 

 2.142 mm. (av. 1.942 mm.) ; width of thorax, 0.782 to 1.054 mm. 

 (av. 0.918 mm.) ; antennae total, 1.445 to 1.581 mm. (av. 1.496 mm.) ; 

 III, 0.357 to 0.408 mm. (av. 0.394 mm.); IV, 0.255 to 0.323 mm. 

 (av. 0.286 mm.) ; V, 0.204 to 0.255 mm. (av. 0.233 mm.) ; VI, base 

 0.136 to 0.153 mm. (av. 0.139 mm.) ; VI, spur 0.289 to 0.323 mm. 

 (av. 0.306 mm.) ; cornicles, 0.187 to 0.255 mm. (av. 0.219 mm.) ; cauda, 

 0.136 to 0.17 mm. (av. 0.153 mm.) ; hind tarsus, 0.119 to 0.153 mm. 

 (av. 0.147mm.). 



Apterous viviparous female. Measurements : Body length, 2.278 to 

 2.448 mm. (av. 2.3403 mm.) ; antennae total, 1.309 to 1.598 mm. 

 (av. 1.4382 mm.) ; III, 0.306 to 0.408 mm. (av. 0.3502 mm.) ; IV, 

 0.221 to 0.306 mm. (av. 0.2618 mm.) ; V, 0.206 to 0.255 mm. (av. 0.238 

 mm.) ; VI, base 0.119 to 0.17 mm. (av. 0.1394 mm.) ; VI, spur 0.289 to 

 0.34 mm. (av. 0.306 mm.) ; cauda, 0.17 to 0.204 mm. (av. 0.187 mm.) ; 

 cornicle, 0.255 to 0.323 mm. (av. 0.289 mm.) ; hind tarsus, 0.153 to 

 0.17 mm. (av. 0.167 mm.). 



122. Aphis frigidae Oestlund 



Oestlund, Geol. Nat. Hist. Snrv. Minn., vol. 14, p. 46, 1886 (orig. desc.). 

 Davidson, Jour. Econ. Ent., vol. 7, p. 132, 1913 (desc. stem mother). 



Eecords. Artemisia californica; Walnut Creek, Contra Costa County (David- 

 son). 



In company with Macrosiphum artemisiae (Fonsc.) this species is 

 found on sagebrush in the San Francisco Bay region. Wilson reports 

 it from Oregon, so probably it is distributed along the coast from the 

 bay north. In the course of observations in southern California 

 during a period of two years the author has been unable to find any 

 aphids infesting sagebrush. 



123. Aphis gossypii Glover 



Figures 192, 193, 215 



Glover, Pat. Off. Eec., p. 62, 1854 (orig. desc.). 



Clarke, Can. Ent., vol. 35, p. 250, 1903 (list). 



Essig, Pom. Jour. Ent., vol. 1, p. 47, 1909. Aphis citri Ashmead (desc.). 



Essig, Pom. Jour. Ent., vol. 3, p. 590, 1911 (desc.). 



Cook, Mon. Bull. Cal. Comm. Hort., vol. 1, p. 65, 1912 (list). 



Games, Mon. Bull. Cal. Comm. Hort., vol. 1, p. 398, 1912 (list). 



Weldon, Mon. Bull. Cal. Comm. Hort., vol. 2, p. 597, 1913 (list). 



Davidson, Mon. Bull. Cal. Comm. Hort., vol. 6, p. 65, 1917 (note). 



