ARGIA. 71 
2. Thoracic dorsum brilliant metallic copper. 
G. Labrum chiefly metallic copper, at least in its basal half, apical half or 
only its front edge yellow. Lower branch of inferior appendage less 
robust than the upper branch. 
H. Segments 3-8 black on dorsum, with only a narrow, basal, blue ring, 
9-10 blue on dorsum. . . . . . . 17. cuprea. 
HH. Segments 3-7 black on dorsum, basal half of 3-6 blue, 8-10 blue 
ondorsum . . » » « . « «[Jocosa, Hagen +.] 
HHH. Segments 3-6 blue on “dorsum, “apical fourth to third black, 
7 black with basal blue ring, 8-10 blue on dorsum . . . . . . 18. cupraurea. 
GG. Labrum yellow or orange throughout. Lower branch of the inferior 
appendage more robust than the upper branch. 
J. Segments 3-6 blue or violet on dorsum, apical fifth black; 7 black, 
8-10 blue on dorsum. . . . 19. @nea. 
JJ. Segments 3-8 black on dorsum, basal half of 3-6 blue; ‘9-10 blue . 20. orichalcea. 
§ II. Total area of dark colours on abdominal segments 38-6 and thoracic 
dorsum Jess than the. pale area on the same parts. 
1. Dorsum of segment 7 chiefly black (except in A. chelata), rear of head 
chiefly black (except in -4. apicalis), postbasal black streaks on 3-6; 
8 and 9 blue, with an.inferior black stripe each side; superior appendages 
distinctly bifid, inner branch longer (except in A. apicalis). 
K. Inferior appendages longer than high. 
L. Black mid-dorsal thoracic stripe wider than the carina. 
Inferior appendages not deeply excised at tip . . . . . . . Qi. Aarknesszi. 
Inferior appendages deeply bifid at tip, lower branch longer than 
upper. 2. ee ee eee ee ew. 22, barrett. 
LL. Black mid-dorsal thoracic stripe not wider than the carina . . . [apicalis, Say *.] 
KK. Inferior appendages higher than long . . . . » . . . . 28. chelata. 
2. Dorsum of segment 7 chiefly blue (except in A. tonto), rear of the head 
pale, no postbasal black stripes on 3-6, 8 and 9 blue, almost unspotted 
(except in A. tonto); superior appendages variable, but when bifid the 
branches are subequal (except in 4. lacrymans). 
[tonto*¥] ) | 
24. lacrymans. , Most readily distinguished 
25. fissa. r by their appendages, 
26. deami. see figg. 48-52, Tab. IV. 
27. tarascana. | 
3. Dorsum of segment 7 blue for its entire length, rear of head largely or 
chiefly black, a continuous inferior black stripe on each side of 3-9 for 
almost their entire length, superior appendages not bifid at tip. 
| 28. variabilis (and medullaris ?). 
4. Dorsum of segment 7 chiefly black (or if blue then with black postbasal 
_T Known from Colombia, may ogcur in Panama and Costa Rica. 
