Pomona College Journal of Entomology 699 



Galls cloiigiitc oval, .■iiitcmiii' smootli witlioiit distinct transverse 



sensoria. papulitransversux 



(i. Kdnniiig ])scu(iogalIs causiiifr tlio ii|)))cr surfaecs of the leaves to fold 

 together along the niid-rilis; antenna! articles III, IV, V and VI 

 with transverse sensoria, spur or unguis with constricted neck. 



■po'pnric(>n(luj>lif()rms 



Curling the leaves or on the younger stems close to the ground ; trans- 

 verse sensoria only on articles III and IV, unguis without constrict- 

 ed neck. fra.rvni-(li pet (dae 



P. betae Doanc. On common beet [licia vulgaris L.). First reported by 

 Clarke on Beet, Red Dock, and Canaigre (Rumez hyvienoscpalus) , from Berke- 

 ley, Placer County, and Palo Alto, California. Can. Ent. XXXV, p. 21.8, 190.3. 

 Davidson reports it from Palo Alto on Dock (Rumex occidetitalis). ,Ir. Ec. Ent., 

 Ill, p. 372, 1910. 



/'. caJifornicus Davidson. First taken on Ranunculus californicus Benth at 

 Palo Alto, California, by David.son. Jr. Ec. Ent., Ill, p. ,S7.'?, 1910. Later taken 

 by tlie writer on the same plant near Nordhoff, California. Originally described 

 as P. ranunculi Davidson, but renamed P. californicus by same autlior. .Tr. Ec. 

 Ent. IV, p. 414, 1911. 



P. populimonilis Riley. "Abundant in Tulare County on Populus fremonti 

 during the summer months at least." Davidson, .Ir. Ec. Ent., Ill, p. 374, 1910. 

 Also abimdant on Populus trichocarpa T. & G. at Santa Paula, California, (see 

 description). Also taken by Davidson in Placer County, California. P. C. Jr. 

 Ent. Ill, p. 398, 1911. 



P. populicaulis Fitch. On Populus trichocarpa T. & G. at Palo Alto, Cal- 

 ifornia. Davidson, Jr. Ed. Ent. II, p. 299, 1909. Also taken in large numbers 

 on the same host at Santa Paula, California (see description). 



P. populitransversus Riley. Abundant on Populus trichocarpa T. & G. at 

 Palo Alto, California. Davidson, Jr. Ec. Ent. Ill, p. 372, 1910. Also taken by 

 same authority in Placer County, California, on Populus fremonti Wats. P. C. Jr. 

 Ent. Ill, p. 398, 1911. 



P. populicnnduplif alius Cowen. Occurring on Populus trichocarpa T. & G., 

 in April. Palo Alto, California. Davidson, Jr. Ee. Ent. Ill, p. 374, IplO. 



P. fraxini-dipetalae Essig. Quite abundant on Mountain Ash (Frarinus 

 dipetala) in the mountains near Santa Paula, California. P. C. Pr. Ent. Ill, pp. 

 353-356, 1911. 



TRIFIDAPHIS Dei. Guercio. 



Type Pemphigus radicicola Essig 



T. radicicola (Essig) Del Guercio. First taken by the writer at Claremont, 

 California, where it occurred on the roots of Amaranthus retroflexus L. (Pigweed) 

 and Solanum douglasii Dunl. (Nightshade). P. C. Jr. Ent. I, pp. 8-10, 1909. 

 Taken also at Oxnard, California, on roots of Nightshade. At Santa Paula, it 

 is frequently found on the roots of Nightshade, Pigweed, and on Potatoes and 

 garden Beets (always underground). 



