No. 39] ODONATA OF CONNECTICUT: LIBELLULIDAE 217 



5. Hind femora 6.75 to 7 mm. ; hind tibiae 8 mm. ; lateral spines on 



9 one-third the length of the margin of this segment minor 



Hind femora 8 mm. ; hind tibiae 9 mm. ; lateral spines on 9 one- 

 sixth the length of the margin of this segment elongata 



6. Labium extending laterally over inner margins of the eyes ; lateral 



appendages of male with outer margin not regularly arcuate, 

 more or less sinuate ; lateral spines, when present, on both 



segments 8 and 9 7 



Labium extending laterally not quite to the inner edge of the eyes ; 

 lateral appendages of male with outer margin regularly arcuate ; 

 lateral spines when present confined to segment 9 9 



7. Length under 25 mm. ; hind femora less than 7 mm. ; abdomen 



without median dorsal prominences ; median appendages of male 



without lateral knobs ; coloration uniform 8 



Length over 25 mm. ; hind femora over 7 mm. ; abdomen with 

 median series of slightly elevated prominences ; median appen- 

 dages of male with a distinct knob on each side (developing 

 furcate apex of inferior appendages) ; coloration not uniform 



cingulata 



8. Lateral spines minute, those of segment 9 one-twelfth to one-_ 



sixth of the remaining length of the segment (hudsonica) 



Lateral spines longer, those of segment 9 one-fifth to one-third 

 the remaining length of the segment margin albicincta 



9. Fringe of hairs on hind margins of abdomen ; tergites not forming 



dorso-lateral tufts ; lateral spines on segment 9 normally present ; 

 lateral setae (labial palpi) 7 or 8 10 



Fringe of hairs on hind margins of abdomen ; tergites 6 to 9 form- 

 ing conspicuous dorso-lateral tufts ; lateral spines on segment 9 

 absent or represented by very minute denticles ; lateral setae 9 



or 10 forcipata 



ID. Fringe of hair on middle section of hind margins of abdominal 



tergites 7 and 8 not forming a thick tuft kennedyi 



Fringe of hair on hind margins of tergites 8 and 9 not forming a 

 median tuft, the hair as long as the median length of the segment 



(franklini) 



Adults, Males 



1. Tips of the superior anal appendages in lateral profile bent sharply 



downward at their distal third (Fig. 53) tenebrosa 



Tips of the anal appendages not bent downwards at distal third ; 

 if bent down, then much beyond this point 2 



2. Superior anal appendages in dorsal view considerably swollen 



before tips and with a dense brush of hairs (Fig. 47) walshii 



Superior anal appendage in dorsal view not swollen noticeably and 

 without a dense brush of hairs 3 



3. Superior anal appendages in lateral profile with subapical inferior 



tooth (Fig. 51) linearis 



Superior anal appendages not with a subapical inferior tooth 4 



4. Extreme tips of superior anal appendages hooked in dorsal view, 



the appendages turning out at tips (extreme tips hooked and 



turned in) (filosa) 



Extreme tip of the superiors not hooked in dorsal view, the appen- 

 dages not turning out at tips S 



5. Abdomen with white basal rings on the segments ; apical third of 



the superiors bent abruptly mesad in dorsal view 6 



Abdomen without white basal rings on the segments ; apical third 

 of the superiors not bent abruptly mesad 7 



