50 Indian Museum Notes. [IVO, IV. 



3. NOTE ON TWO NEW SPECIES OF GALL-APHIDS 



FROM THE NORTH-WESTERN 



HIMALAYAN REGION. 



By G. B. Buckton, f.r.s. 

 With one plate — No. IV. 



Pemphigus napceus, n. sp. 



This homopterous insect forms smooth rounded galls on the twigs 

 of the Poplar tree growing at an elevation of 9,000 feet in the Valley 

 of the Yasin river, near the Darkot Pass. 



The galls have a shining green surface, slightly veined with 

 brown, and variegated with yellowish patches. 



They are mostly roundish ; but some occur of irregular shapes, 

 about I '10 X 0*50 inches in measurement. 



When cut open, they show a single chamber tenanted by 20, or 

 more, insects, some of which are in the pupal and others in the winged 

 form. The alate insects are of two sizes, one being about twice 

 the bigness of the other. A much larger female, which is blind and 

 apterous, may be also found. 



She is the foundress of the colony, and originally produced 

 the first walls of the gall structure. 



An aperture at the side affords an exit for the winged females 

 when they are matured. 



The winged female may be thus described : — Body robust. 

 Head and thorax, both above and below, shining black. Abdomen 

 pale, greenish yellow, smooth, and immaculate. Antennae black, 

 and about the length of the abdomen. First two joints globose, 

 third joint ringed and about equal to the fourth and fifth taken 

 together, the sixth ending in a blunt nail, and equal to the fifth. 

 Eyes large, with the usual superimposed tubercle. Nectaries, 

 none. Legs black, with rather long tarsi. Upper wings ample, 

 with rounded tips. Veins, fine and black, with a conspicu- 

 ous dark stigma. The neuration approaches that of a Schi- 

 zoneura, inasmuch as the third vein does not meet the cubital. 

 Notwithstanding this peculiarity, I regard this insect as a Pem- 

 phigus, and nearly allied to P. spirotheca of Koch, which in Europe 

 also forms globular galls on the poplar {Populus nigra)* 



