No. 39] ODONATA OF CONNECTICUT: GOMPHIDAE I5I 



scars not conspicuous, though present and not divided into sep- 

 arate areas by lines of hairs ; lateral spines present on segments 

 6-9 inclusive, that of segment 9 nearly or quite as long as segment 

 10 measured on the dorso-meson ; lateral terminal appendages 

 three-fourths as long as the inferiors. 



Measurements; exuviae: total length, 23 mm. ; length of abdo- 

 men, 14 mm.; greatest width, 6.5 mm.; length of hind femora, 

 5 mm. ; width of segment g on front margin, 4 mm. ; hind margin, 

 2.5 mm.; length measured on the dorso-meson, 1.5 mm.; length 

 of segment 10, i mm. 



Connecticut. — Two exuviae collected at Colebrook, 19 June, 1920. 



Adult, male. — Color black and green. 



Head : clypeus, labrum, and labium pale yellow ; front with 

 dorsal dark stripe in front of ocelli, vertex yellow and with a 

 distinct ridge. 



Thorax : pronotum with 2 small mesal spots and a lateral spot 

 on each side ; mesepisterna with a broad yellow stripe connecting 

 with the half-collar by its full width, a narrow pale stripe above 

 the suture and a small spot cephalad of the wing iDases ; legs black. 



Abdomen : black ; segments i and 2 with yellow on the dorso- 

 meson and on sides ; 8 and 9 with yellow triangular spots on sides ; 

 4-7 with dorsal yellow spots at base ; 8 and 9 expanded ; superior 

 anal appendages (Fig. 21, No. 18), with a conspicuous tooth at 

 middle. 



Female. — Similar to the male; vulvar lamina (Fig. 20, No. 4) 

 long and slender ; abdomen with yellow spots on cephalo-lateral 

 angles of 4-7 inclusive, and yellow lines on meson of 2-5 ; abbre- 

 viated yellow lines on 6 and 7 and spots on 8 and 9 at bases, which 

 may, however, be wanting. 



Measurements : total length, male 40, female 43 mm. ; length 

 of abdomen, male 28, female 30 mm. ; length of hind wings, male 

 25, female 25-26 mm. ; width of hind wings, male 7, female 8 mm. 



Connecticut. — Litchfield, i July, 1916; 10 June, 11 July, 1924 (L. B.W.). 



New England. — May 31-July 8. 



Group 2 ExiLis-DESCRiPTUS Group 



Gomphus descriptus Banks 

 Journal New York Entomological Society, 4: 194-195: 1896. 

 Nymph. — According to Needham, the nymph of this species 

 has the third antennal segment depressed and somewhat widened 

 apically ; labium with mentum having the distal margin nearly 

 straight, fringed with flat hairs but unarmed ; palpi with terminal 

 hook of proximal segment regularly incurved, and with six to 

 eight teeth before it on the inner margin. 



Abdomen: lateral spines on segments 6-9 sometimes obscured 

 by tufts of hairs on the sixth segment, those on the ninth segment 



