No. 39] ODONATA OF CONNECTICUT: LIBELLULIDAE 243 



2. Distal margin of the mentum crenulate (PI. vii, Fig. 5) exusta 



Distal margin of the mentvmi not crenulate, not as in PI. vii, Fig. 5 3 



3. Lateral setae of the labial palpi five 4 



Lateral setae more than five 5 



4. Segment 9 on ventral side eqtial in length to 9 and 10 on the 



dorsum; setae on distal margin of lateral lobes of labium in 



groups of three vibrans incesta 



Segment 9 on ventral side longer than 9 and 10 on the dorsum; 

 setae of distal margin of lateral lobes in groups of five . .auripennis 



5. Lateral setae of the labial palpi six cyanea 



Lateral setae seven luctuosa 



6. Lateral setae of the labial palpi seven quadrimaculata 



Lateral setae eight or nine (PI. vii, Fig. i) pulchella 



Adults 

 Males and Females 



1. Wings clear, without spots, occasionally with dark tips, never with 



dark basal marks 2 



Wings spotted with dark pigment, always with dark basal marks . . 3 



2. Wings suffused with gold, veins reddish yellow; stigma orange or 



brown (PI. xxi, Fig. 5) auripennis 



Wings clear, veins not reddish yellow; stigma black (PI. xxi, 

 Fig. 2) vibrans incesta 



3. Stigma bicolored, yellow or cream-colored and black 4 



Stigma unicolored, usually black 5 



4. Stigma of front wing 4 to 4.5 mm., proximal half or three-fifths 



yellow or cream-colored (PI. xxi, Fig. 6; PI. xv. Fig. 3) ..cyanea 

 Stigma of front wing 5.5 to 6 mm., proximal three-fourths to five- 

 sixths yellow fiavida 



5. Wings with black bases, the black or fuscous area occupying the 



entire width of the wing (PI. xxi, Fig. 3) luctuosa 



Wings with dark streaks at bases or without spots, the spots if 

 present not occupying the entire width 6 



6. Tips of wings clear and without cross-bands at stigma 7 



Tips of wings dark or with dark cross-bands at stigma 8 



7. Wings with a dark triangle at the base of the hind wings ; no mark 



at the nodus (PI. xx, a) exusta 



Wings with a dark triangle at the base of the hind wings and 

 also a spot at the nodus, PI. xxi. Fig. 4 quadrimaculata 



8. Nodal spot not extending behind R (PI. xxi. Fig. 8) vibrans vibrans 

 Nodal spot extending behind R, about half tlie width of the wing 9 



9. Extreme tip of wings almost clear ; wings suffused with gold at 



their bases; no whitish areas between the darker spots (PI. xxi, 



Fig. 9) semifasciata 



Extreme tip of wings usually covered with the apical band; wings 

 not suffused with gold at their bases ; usually marked with whit- 

 ish areas between the darker spots (PI. xxi, Fig. 7) pulchella 



Libellula auripennis Burmeister 



Handbuch der Entomologie, 2 : 861 : 1839. 



Nymph. — Lateral setae of the palpi five; mental setae 8 to lo; 

 dorsal hooks on segment 3 or 4 to 8. 



Measurements (Needham, 1901) : total length, 27 mm,; length 

 of abdomen, 17.3 mm. ; width of abdomen, 7 mm. ; length of hind 

 femora, 6 mm. 



