Pomona College Journal of Entomology 527 



two-thirds the length of the body, articles I and II color of head, III and IV 

 lemon yellow, the latter dusky at tip, remaining articles dusky, lengths: I, 0.05 

 mm.; II, 0.01 mm.; Ill, 0..S8 mm.; IV, 0.22 mm.; V, 0.2 mm.; VI, 0.1.2 mm. (spur 

 0.2,9 mm.), tot.il 1.28 mm. Roxtriim — Light yellow, brown at base with dark tip, 

 reaching to third coxa-. Prothora.r — Witli lateral tubercle, deep brown. Meso- 

 thorax — Same color as the i)rothnr.ix. Metalhorax — Much lighter in color, amber. 

 Abdomen — Pale green with dark transverse dorsal markings, lateral dark 

 marginal markings on ventral surface, small tubercle on lateral margin near 

 middle. CornicJcs — (Figure 170 C). Cylindrical, black, curved outwardly, slightly 

 wider at base than at ajn-x, length 0. l.') mm. I-^egs — Coxsb brown; femora of two 

 first pairs yellow, with dusky tips, ajjical two-thirds of third pair dusky; tibiae 

 dark at extreme bases and tips ; tarsi dark. Style — Half as long as cornicles and 

 as long as tarsi, dark. 



Host — On the undersides of the older leaves of Ceanothus hirsutus Nutt. 

 Usually scattering and not in thick colonies. 



I^ocality — Santa Paula Canyon, in mountains near Santa Paula, Cal., at an 

 altitude of from 700 to 1500 feet. Date of collection — April 29, 1911. Serial 

 number 32. 



This form was first believed to be Aphis ceanothi Clarke, but according to his 

 original description in Canadian Entomologist XXXV, p. 250, 1903, the following 

 differences are noticeable and appear to justify separation: 



Aphis ceanothi Clarke Aphis ceanothi-hirsuti n. sp. 



General — Winged form larger than Apterous form much the largest, 



apterous. Antennal article IV slightly longer 



Winged — Antennal articles IV and V than V. 



sub equal. Cauda plainly visible and dusky. 



Cauda inconspicuous and yellow- Abdomen with distinct dark dorsal 



brown. markings and black posteriorly. 



Abdomen clouded yellow-brown. Veins yellow and dusky. 



Veins dark green. 



. , . , TTT 1 Article IV longer than V. 



Apterous — Antennal articles IV and 



Legs and antenn» not of a uniform 

 V sub-equal. , 



color. 

 Legs and antenna of a uniform color. t> i i ■■ , , , 



1 V 1 body elongated to globular. 



" . , . , On older leaves of Ceanothus hirsutus 



Hosts — Infesting tender tips and on 

 blossoms of Ceanothus integerrimus. 



Xutt. Never found on blossoms, al- 

 though there were plenty on the trees. 



Aphis medicaginis Koch. 



1857 Aphis medicaginis Koch, Pflz., p. 94 



1879 Aphis medicaginis Koch, Monell, LT. S. Geol. Surv. V, No. 1, p. 24. 



1880 Aphis medicaginis Koch, Thomas, 8th. Rept. Ent. 111., pp. 101, 192. 

 1910 Aphis medicaginis Koch, Williams, Aphid. Nebr., pp. 50-51. 



