302 MAINE AGRICUI.TURAL EXPERIMENT STATION. I9II. 



the basal cell R; the cubitus forks proximad of the fork of the 

 media (Figs. 221 to 223). Distinguished from Syntciiina by 

 the position of the lateral ocelli, in having the costa less pro- 

 duced beyond the tip of the radial sector, and in the arrange- 

 ment of the setulK of the wing in parallel rows. 



Table of species. 



a. Length 6 mm; thoracic stripes subobsolete. i. perspicua. 



aa. Length less than 5 mm. 



b. Cubitus forks noticeably proximad of the proximal end of the 

 crossvein ; species over 3 mm. in length, 

 c. Fore metatarsus less than .8 of tibia in length ; abdomen dark 

 brown, hind margins of the segments broadly yellow ; female. 



2. cincta n. sp. 

 cc. Fore metatarsus over .8 of the tibia in length ; abdomen yel- 

 low, each segment with a large sub-triangular spot ; male. 



3. triangularis n. sp. 

 bb. Cubitus forks at or distad of the proximal end of the crossvein. 

 c. Species over 3 mm. in length. 



d. Cubitus forks at the proximal end of the crossvein ; abdo- 

 men dark brown, each segment except the first with yel- 

 low margins. 4. vulgaris. 

 dd. Cubitus forks distad of the proximal end of the crossvein. 

 e. Thorax brown, humeri yellow ; abdomen yellow, each seg- 

 ment with a large triangular brown spot ; hind tarsi 

 slightly shorter than its tibia. 5. obesa. 

 ee. Thorax yellowish, with 3 vittas sometimes subcoalescent. 

 f. Abdomen largely brown, apical margin and large pos- 

 terior lateral triangles, yellow ; hind tarsi longer than 

 tibia; Cu2 somewhat sinuate. 6. bellula n. sp. 

 ff. Abdomen brown, segments yellowish at base. 7. focda. 

 cc. Species less than 3 mm. in length. 



d. Cubitus forks under the proximal end of the crossvein ; 

 hypopygium with slender clasper, each with about 10 

 strong setae (Fig. 113). 8. diffissa n. sp. 



dd. Cubitus forks only slightly proximad of fork of media; 

 each chisper with a clavate basal lobe (Fig. 114) ; ventral 

 aspect of hypopygium, apically, densely setose. 



9. patens n. sp. 

 Trichonta Dazvsoni is a fossil from British Columbia. 



I. Trichonta perspicua Van der Wulp. 



Tijdschr. v. Ent. XXIV. 142. 1881. 



Male. Length 6 mm. Reddish yellow; antennae 1.5 times as 



long as head and thorax, scape and basal joints yellow, re- 



mainfler of flagellum fuscous. Thorax yellowish, with indica- 



