500 M. W. R. de V. GRAHAM 



thorax. Fore wing with lower surface of costal cell with its row of hairs 

 complete, or at most very slightly interrupted in the middle 



H. cardui (Erdos) (p. 540) 

 Propodeum with the longitudinal carinulae of the median area, if present, are 

 irregular or do not reach the costula, or else the latter is weak or absent. 

 Gaster sometimes longer than head plus thorax. Fore wing with lower 

 surface of costal cell with its row of hairs sometimes widely interrupted in 

 the middle or before the middle . . . . . . . . 14 



14 (13) Propodeum (Text-figs. 374-377, 379-381, 385, 386) with posterior part of 



plicae, at sides of nucha, converging slightly to strongly towards the 

 median line. Fore wing with line of hairs on lower surface of costal cell 

 sometimes widely broken medially, or before the middle . . . . 15 



- Propodeum (Text-figs. 378, 382-384, 387-389) with posterior part of plicae, at 



sides of nucha, parallel or virtually so. Fore wing with line of hairs on 

 lower surface of costal cell always complete ...... 49 



15 (14) Propodeum (Text-fig. 385) with posterior part of plicae converging only 



slightly ; median area without a costula, its panels uniformly reticulate. 

 Fore wing with line of hairs on lower surface of costal cell complete. Anten- 

 nal scape often reaching the level of the vertex or slightly above it. Gaster 

 usually at least slightly longer than head plus thorax .... 70 



- Propodeum (Text-figs. 374-377, 379-381, 386) with posterior part of plicae 



converging quite strongly ; median area often with a costula, its panels often 

 irregularly sculptured. Either the line of hairs on the lower surface of the 

 costal cell is broken medially ; or the antennal scape does not quite reach 

 the level of the vertex ; or the gaster is not longer than head plus thorax 16 



16 (15) Fore wing with row of hairs on lower surface of costal cell (Text-fig 403) broken 



medially or before the middle, often widely so . . . . . 17 



- Fore wing with row of hairs on lower surface of costal cell complete . . 26 



17 (16) Gaster as long as, or longer than, head plus thorax ; usually 2 to 4-5 times as 



long as broad, only occasionally a little less than twice . . . . 18 



Gaster at least slightly shorter than head plus thorax, 1-2 to 1-9 times as long 



as broad ............ 36 



18 (17) Pronotal collar very long, medially one quarter as long as mesoscutum, or 



slightly more. Large species, over 3 mm. in length ; gaster nearly three 

 times as long as broad, longer than head plus thorax ; proximal segments 

 of antennal funicle subquadrate, the first segment hardly as long as the 

 pedicellus ; body mainly coppery green. (Madeira) H. integer (Walker) (p. 538) 

 Pronotal collar at most slightly more than one fifth as long as mesoscutum ; 



if as much as one fifth, then the gaster is at most 2-65 times as long as broad 19 



19 (18) Pronotal collar longer, medially as a rule one fifth or slightly more than one 



fifth as long as mesoscutum, slightly less in dwarfs ; very sharp anteriorly 

 and sometimes with a slightly raised carina anteriorly. Antennal flagellum 

 testaceous at least beneath ; head and thorax often dull or bronze-green, 

 sometimes brighter green to blue. Length usually 2-5 mm. or more, 

 rarely less ............ 20 



- Pronotal collar shorter, medially one seventh to one sixth as long as mesoscutum, 



sometimes not sharp anteriorly. Antennal flagellum often black ; head 

 and thorax usually bright green to blue, olive to bronze in the Madeiran 

 species alter nipes. Length sometimes less than 2-5 mm. . . . . 21 



20 (19) Head in dorsal view (Text-fig. 408) 2-15 to 2-25 times as broad as long ; 



temples at most somewhat more than one third as long as eyes, tending to 

 converge rather distinctly, especially in smaller specimens. Gaster only 

 i-i to 1-2 times as long as head plus thorax, 2 to 2-35 times as long as 



