256 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



26. Antenna of alate forms with six segments (except Melaphis 



niinuta) ; cauda and anal plate not obvious; when sensoria are 

 linear, the annulations do not completely encircle the segment .. 



PEMPHIGINAE, p. 311 

 Antenna of alate forms with three to five f. 27 



27. Cauda and anal plate obvious; linear annulations of all antennal 



segments distad, the second completely encircling the segment ... 28 

 Antenna with numerous subcircular prominent sensoria, five- 

 segmented [Forda] 



28. Antenna five-segmented Hamamelistes HORMAPHIDINAE, p. 328 

 Antennae three-segmented Hormaphis HORMAPHIDINAE, p. 328 



Tribe LACHNINI. 

 By Harley Frost Wilson, M.S. 



Probably because the species of this group live mostly on 

 conifers and forest trees or shrubs, they have not been collected to 

 any great extent and only a few species have actually been collected 

 in Connecticut. However, all of the species given here have been 

 taken in adjoining states and therefore must occur in this state as 

 they range from Maine southward as far as Virginia and westward 

 to Minnesota. 



Some of the specific names given have not heretofore been used 

 for American species but the writer has been working on a mono- 

 graph of this group for several years and has found that a number 

 of our American forms are but synonyms of European species. 



Key to Genera. 



1. Tarsi of hind legs with both segments distinct 2 



Tarsi of hind legs apparently with but one segment or the first 



minute or wanting [Trama] 



2. Stigmal vein arising from the body of the stigma and back of the 



stigmal point,* which is tapering (on deciduous trees or shrubs) 3 

 Stigmal vein arising from the base of the stigmal point which is 

 always truncate. (On conifers) 6 



3. Stigma long and slender, sides parallel or nearly so 4 



Stigma stout and comparatively short, outer or inner edge rounded, 



the opposite side nearly straight 5 



4. Stigma long and slender and curving round the point of the wing 



and stigmal point extending far beyond the base of the radius . . 



Longistigma, p. 257 

 Stigma long and slender, not extending around the point of the 

 wing; stigmal point extending but a short distance past the base 

 of the radius Tuberolachnus, p. 257 



5. Stigma with the outer edge rounded and the inner edge straight to 



the base of stigmal point. Median vein with two forks 



Nippolachnus, p. 258 

 Stigma with the inner edge rounded and the outer edge straight, 

 median vein once forked Anoecia, p. 258 



6. Rostrum with the last three segments forming a long slender spear- 



shaped point (always bark feeders) 7 



Rostrum with the last segment short and blunt, the third and 

 fourth segments quadrate 8 



* The stigmal point as here defined is the tapering point set off by a line 

 extending from the inner edge to the outer edge of the stigma. 



