10 
SUBFAMILY GOMPHINAE 61 
Stigma very broad, doubling width of space between bordering 
longutaidinal Veins s:. 24 .vea lds aee tte Erpetogomphus, p. 78 
Stigma normal, widening this space by not more than half...... 9. 
Hind femora armed with many short spines... .. Gomphus, p. 81 
Hind femora armed with 5-7 long strong spines............... 
eee ik oo? asl eRe eS: Dromogomphus, p. 117 
First post anal cell little wider than long. Eastern. Lanthus, p. 119 
First post anal cell twice as wide as long. Western............ 
RUDE Rig ented na? 2 TEER ARERR eee eMC Rea, Octogomphus, p. 121 
Nymphs 
Abdomen circular; third antennal segment circular; legs not 
TORSOTIA: is isk eN Abe A ce cet uae se SOP Hagenius, p. 66 
Abdomen much longer than wide; third antennal segment 
elongate leas fossomales te ee aces eG alanis 20 Res ee 2. 
Tenth abdominal segment longer than all the others together 
ie cava cig ee pa atakacaes ie Race Note La Genus’, p. 60 
Tenth abdominal segment not longer than other single seg- 
PEVOTUGS oh asics sete ra WANE UIE Ane eS RR re Mec ays accitehens eae eee 3. 
Wings cases diverpentariaiuce aumiaesar, . 46.) cme S Toe 4, 
Wanecases notrdiverzentied® shia) .c Se. ate. LOL. a5 See 5. 
Fourth antennal segment cylindric........... Progomphus, p. 62 
Fourth antennal segment a spherical rudiment Ophiogomphus p. 67 
SE Om Tae PN sincere dt evs tae se and Erpetogomphus, p. 79 
Phird antennal :segment thin, flat, oval... 3: oewdsem: eats: 6. 
Third antennal segment elongate or linear................... i 
Par eastern 22224 | aaett eee mueee pees Wie 2 Lanthus, p. 119 
MET WESUCEE... .. 5 ss ios ct ccm tttn eta ae Octogomphus, p. 121 
Segment 9 with a sharp middorsal ridge ending in a straight 
apicalispiine sxotsn .vcursact! by wee ddeh a Se ee 8. 
Segment Oo notao. 4 1 At et. oe Pee Gomphus, p. 81 
Lateral abdominal appendages as long as the inferiors.......... 
iy SA ae SE EU alt), tk a Gomphoides, p. 63 
Lateral abdominal appendages shorter than the inferiors....... 
1) OOD 1D BOUNY BEE. OAC AM Woe ee Dromogomphus, p. 117 
