Triacanthagyna and Gynacantha 35 



pale flesh, narrowly black above, with an irregular black bar to the 

 foramen. Prothorax flesh or very light brown, hind lobe darker. Thorax 

 above green, a narrow interrupted half collar of light yellowish green, 

 bordered above with a brown transverse stripe three or four times as wade 

 which is narrowly continued up the middorsal carina to spots below the 

 antealar sinus ; on either side a broad indefinite brown antehumeral stripe 

 which fades out above in the green, and is darker below ; mesepimeron 

 light greenish brown, greener above, shading out to brown below; mete- 

 pisternum and mctepimeron pinkish flesh brown, traces of green about the 

 stigma ; beneath the same pinkish flesh ; sclerites between front wings 

 bright grass green, between hind wings brilliant evanescent blue. Abdom- 

 inal segment i flesh, apical third or half brown above ; 2 brown above, a 

 narrow longitudinal median green line which passes posteriorly into a 

 broad blue subapical ring, the extreme apexl black ; basally a narrow 

 transverse green line on either side, widely separated from the median 

 green line; posterior to mid-length on either side a narrow transverse green 

 stripe or line, narrowly bordered black, and less widely separated than the 

 basal lines from the median line ; auricles bright blue above, edged with 

 black (margins of genital fossa without denticles or spines; auricles with 

 seven to nine denticles, with several long black hairs on the dorsal surface 

 near or between the basal teeth) ; 3 with a large lateral basal blue spot on 

 either side, and traces of pale light brown spots at the transverse carina, 

 base and apex shaded into darker brown; 4 brown, shading into darker at 

 base and apex, a minute green spot on either side at the tranverse carina; 

 5-7 brown, shading into darker apically and a darker line at the transverse 

 carina; 8 and 9 slightly darker brown; 10 slightly paler than 8 and 9 except 

 at apex ; at the transverse carina, on either side of 8 trace of a pale spot. 



Female abdominal appendages narrow, of nearly uniform width through- 

 out, about .5 wide, narrowed on the inner margin in the basal seventh, the 

 apical seventh tapering to the acute apex, the tapering mostly on the inner 

 edge, the outer edge being relatively straight throughout the length of the 

 appendage. 



Aeschna viridis Rambur was described from a single male with the last 

 seven abdominal segments gone, and "sans indications de patrie." De Selys 

 (Rev. des Od.) stated that it is an exotic species very difi^erent from A. 

 ziridis Eversmann, but there is nothing to indicate that de Selys regarded 

 it as a Gynacantha. The next mention of the species is by Kirby (23) who 

 records specimens from Para and Tapajos. referring them to Gynacantha. 

 At my request these specimens were studied by Air. Campion who kindly 

 sent me one for study. He reports that there is no reason to think any 

 of these specimens were ever seen by de Selys. The male loaned me by Air. 

 Campion is G. auricidaris Martin. If it should be shown that these speci- 

 mens in the British Museum, or any of them, had been compared with 

 Rambur's type, now lost (Martin, 25), and determined by de Selys as 

 subviridis, then auricidaris would become a synonym. However the descrip- 

 tion of subviridis {viridis) seems to exclude this identification and we have 

 in addition Mr. Campion's opinion that de Selys never saw the Para and 



