1 SSECT < iALI.8. 37 



Potentilla canadensis. 



Cecidomyiaf potenlillaecaulis, n. s. 



This gall consists of the much enlarged internodal space of stem. 

 Apparently one-celled, altho with several longitudinal cavities not con- 

 nected with main cell. Outside surface and color like remainder of the stem. 

 One specimen. September. On cinquefoil, Potentilla canadensis. 



Gonaspis potentillae Bassett. Cinquefoil axil-gall. 



Diastrophu's potentillae Bassett, Proc. Ent. soc. I'hil., 1864, v. 3, p. 689 690. 



< >stt'ii Sacken, Proc. Ent. soc. Phil., 1865, v. I. p. 361. 



Cook, Ohio nut., 1904, v. 4, p. 120, fig. 87. 



Jarvis, 38th aim. rept. Ent. soc < Intario, 1907, p. 88, pi. B, liy. 5. 

 Gonaspis potentillae Ashmead, Psyche, 1897, v. 8, p. 68. 



A subspherical gall in axil of leaf of Potent ilia canadensis. 8-1 1 mm. 

 in diameter. Monothalamous. Green with sometimes m tinge of red, 

 turning brown in autumn. Common. Insect emerges the following spring 



Rosa. 

 Rhodites bicolor Harris. ^pi'iy rose-gall. 



Cynips bicolor Harris, Rept. ins. Mass. inj, veg., 1841, p. 399; Treat, ins. N. E. Lnj. veg., 1*42, p. 



399; same, 1852. p. 435; Treat, ins. inj. veg. (Flint ed.), 1862, p. 548-549. 

 Rhodites bicolor Osten Sacken, Croc. Ent. soc. Phil., 1863, v. -2, p. 43, 48 19. 



Riley, Amer. ent., 1870, v. 2, p. 246, 309, fig. 192. 



Beutenmiiller, Bull. Amer. mus. nat. hist., ls'.)2, v. 4, p. 246, pi. 9, fig. I. 



Townsend, Psyche, 1895, v. 7, p. 272, 307. 



Cook, Ohio nat., Unit, v. 4, p. 123, 141, fig. 120. 



Jarvis, 37th aim. rept. Ent. soc. Ontario, 1906, p. 70, pi. E, tig 2. 



Spherical, 10-14 mm. in diameter, covered with long spines. Mono- 

 thalamous. In summer green with tinge of red usually, brown later. 

 Frequently deforms the whole leaf of wild roses, Rosa, several species. 

 Common. Insect emerges in late summer. 



Rhodites dichlocerus Harris. Long rose-gall. 



Cynips dichlocerus Harris. Rept. ins. Mass. inj. veg., 1841, p. 399400; Treat, ins N. E. inj \ ■ g 

 1S42, p. 399-400; same, 1S.V2, p. 485; Treat, ins. inj. veg. (Flint ed 

 1862, p. 549, pi. 8, lis. 6-8. 

 Rhodites dichlocerus Osten Sacken, Proc Ent. soc. Phil., 1863, v. 2, p. 41, 4t;. 



Beutenmiiller, Bull. Amer. mus. nat. hist., 1892, v. 4, p. 247. pi. 9, fig. •"). 

 Diastrophus dichlocerus Beutenmiiller, Psyche, 1908, v. 15, p. in. 



Woody, elongated, roughened gall, tapering to union with stem. 

 Polythalamous. About 2-3 cm. long; 1 cm. wide. On stem of several 

 species of wild rose, Rosa. 



Rhodites ignota Osten Sacken. Mealy rose-gall. Fig. 73. 



Rhodites ignota Osten Sacken, Proc. Ent. soc. Phil., 1863, v. 2, p. 43, 49. 



Beutenniiiller, Bull, Amer. mus. nat. hist., lsa2, v. 4, p. 246, pi. '.». fig. 2. 



A spherical woody gall covered with white mealy substance. From 

 5-8 mm. in diameter. Sometimes two or more galls grow together. One 

 or several on leaves of wild roses. Common. 



Rhodites lenticularis Bassett. Rose lentil-gall. Fig. 77. 



Rhodites lenticularis Bassett, Trans. Amer. ent. soc, 1890, v. 17, p. 59-60. 

 Beutenmiiller, Ins. galls vie. N. Y., 1904, p. 8, tig. 

 Jarvis, 38th aim. rept. Ent. soc. Ontario, 1907, p. 89. 



