43^ CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



encircle the twigs or stems on which they occur, are from 25 to 

 75 mm. in length or even longer. 



This species no doubt occurs throughout the state especially 

 on Rubus villosus. Woodbridge, 13 May, 1907 (W. E. B.), Mystic, 

 3 March, 1915 (I. W. Davis). 



*D. potentillae Bassett. Cinquefoil Axil Gall. 



Female: length nearly 3 mm.; very like the male, differing 

 essentially only as follows: antennae 13-jointed, ocelli arranged 

 as though along a straight line; legs somewhat darker. Male: 

 length approximately 2.7 mm. ; head black, vertex nearly smooth, 

 face finely scratched and with a carina extending from the vertex 

 to the mouth, mouth parts faintly tinged with reddish brown, 

 antennae 14- jointed, the first, second and third joints black, the 

 following joints dark cinnamon, the third joint not deeply incised ; 

 thorax black, pronotum hairy, mesothorax shining, parapsidal 

 grooves originating at the pronotum and converging toward the 

 scutel, the space between these two parapsidal grooves nearly 

 smooth and hairless and with faint longitudinal grooves, scutel 

 sculptured and with basal pits, when viewed laterally appearing as 

 a cone the axis of which is at an angle of 45 to the axis of the 

 body; legs very dark brown or black, coxae black, femora and 

 tibiae yellowish brown above, tips of tarsi black or nearly 

 black ; pleurae very finely scratched ; wings pale dusky, veins dis- 

 tinct but not extending to the margin of the wings, the vein 

 forming the base of the radial area with a heavy brown blotch, 

 first transverse vein reddish brown, areolet present, radial area 

 open, cubitus disappearing before attaining the first transverse 

 vein; abdomen petiolate, perfectly smooth and shining black, the 

 second and third segments connate. 



The galls of this species occur on Potentilla canadensis and 

 have the following characteristics: about 7.5 to 15 mm. in diam- 

 eter, rather longer than thick, growing in the axilis of the leaves, 

 of a soft spongy consistency when dry, and with a single cell 

 inside that is not free from the surrounding substance. 



Type locality: Waterbury. 

 *D. similis Bassett. 



Female : length 3 mm. ; head black, vertex finely roughened, 

 ocelli nearly arranged as though along a straight line, face rough- 

 ened and carinate, mandibles black; antennae 13-jointed, second 

 joint half fcs long as the first, third to twelfth joints inclusive 



