556 Pomona College Journal of Entomology 



Reaching to metatliorax, lemon yellow, dusky at tip. Thorax — Gradually widens 

 from prothorax backwards, segments compact and pushed up dorsally to form 

 transverse lobes. Abdomen — Globular, as wide as long, several transverse depres- 

 sions on dorsum, smooth. Legs — Short, stout, hairy. Style — Rounded, hairy, 

 not visible in more robust forms, but distinct in smaller individuals. 



Apterous females are very scarce and I was able to obtain but a very few. 

 Those found were in the curled leaves and producing great numbers of young. 

 They appear to be true stem-mothers. 



Host — On Mountain Ash {Fraxinus dipetala H. & A.). Winged forms and 

 nymphs were found feeding on the undersides of the leaves, which they curled into 

 knots of various shapes, upon the stems of the younger growth, at the bases of 

 the suckers and hidden by the decayed and fallen leaves, while some forms were 

 taken around the trunk of the trees at quite a depth underground. The nymphs, 

 especially, were often found in large colonies on the young stems. The few adult 

 apterous forms were found only within the masses of curled leaves, which usually 

 occur at the tips of the new growth. 



Locality — The infested ash trees are located on the north slope of the moun- 

 tains, six miles north of Santa Paula, at an elevation of from 1000 to 2000 feet. 

 Date of collection — May 7, 1911. Serial number 33. 



This species differs from Pemphigus fraxinifolii Thos. in the following: 



Pemphigus fraxinifolii Thos. Pemphigus fraxini-dipetalae n. sp. 



Wings — Transparent with mealy Dusky, with bluish tinge, transpar- 



wliite tinge. ent. 



Third discoidal vein arising near base Third discoidal not arising near base 



of second, almost invisible, not obsolete of second, plainly visible and distinct, 



at the base. obsolete at base. 



Obliques in hind wing connected. Obliques in hind wing arising from a 



Wing expanse 5.7 mm. common dark spot, their bases may be 



Body — Length of body 2 mm. Abdo- at a common point or somewhat distant, 



men dark green, with large roundish Wing expense 12. mm. 



spots on each side. Length of body 3.5 mm. Body almost 



Aiitennae— Article III of winged or black, side spots very small, 



form as long as IV and V together. Article III of winged form not as 



Medium in size. long as IV and V together. 



Very large. 



APHID SYNONYMY 



In connection with the Host Index to California Aphididae and the synonymy 

 of the genera and species, it was stated that all additions and corrections would 

 be added as fast as possible. I am therefore taking this opportunity to make the 

 first additions and corrections. 



In a letter from Mr. John Davis he called attention to the following: 

 First — That Calaphis betulaecolens Fitch is wrong in that the species 

 hetulaecolens does not belong to this genus, it being a fact that only the species 

 betulella Walsh belongs to the genus Calaphis. 



