66 Bulletin Wisconsin tiatural History Society. [Vol. 0, Nos. i— 2. 
the tibiae ; in fnrcifer they are black. From spicatus it is disting-uished 
by the vulvar lamina and the occiput. Spicatus has a spine on the 
occiput, the vulvar lamina are about one-third the length of segment 
9, deeply bifid, the apices well separated and acute. 
Life Zone : Boreal, Transition, Upper Austral. 
Wisconsin : Divide, June 24-30, 1907. 
Time and Habitat — May to July about lakes and streams. 
Gomphus descriptus Banks and borealis Needham greatly resemble 
sordidus. They differ by the black dorsum of segments 9 — ^10 of the 
abdomen and the black appendag'es. The female has a narrov^ yellow 
stripe on 10, the vulvar lamina are one-third the length of 9, the apical 
half bifid, acute aud divaricate. The male descriptus has an acute 
inferior tooth on the superior abdominal appendage, while sordidus 
has an inferior lobe. In horealis the inferior tooth is directed far 
inward. Both s]iecies have black tibiae. 
Gomphus exilis Selys, Bull. Ac. Belg. 21 (2), p. 55, 1854'; Hagen, 
Syn. Neur. N. Am., pv 108, 1861; Needham. Bull. 47 N. Y. State Mus., 
p. 455, 1901 (Bibliography & Desc. of nymph) ; Needham & Hart, Bull. 
111. State Lab. 6, p. 82, 1901 (Desc. of nymph). 
Abd. male 31—32, female 32—33 ; h. w. male 25—26, female 26—27. 
Male. — Dark brown and greenish yellow. Face and occiput olive. 
Thorax with a mid-dorsal brown stripe, wider below, connected above 
with the antehumeral, separated by the green carina. Humeral and 
antehumeral and lateral sutures brown. Legs brown, the tibiae olive 
externally. Wings with costa olive, pterostigma brown. Abdomen 
darker, dorsum with a yellow stripe on 1 — 8. Sides yellow, most of 9 
yellow. 
Female. — Like the male. Abdomen with more yellow on the sides, 
and the dorsum of 9 — 10 yellow. Legs paler, the fore and middle 
femora green below, hind femora luteous except at the apex, all the 
tibiae green or yellow above, the feet black. Vulvar lamina one-fourth 
the length of 9, triangular, bifid, and apices rounded. 
Life Zone: Transition and Upper Austral. 
Wisconsin : Divide, June 24-30, 1907. 
Time and Habitat — May to July about lakes and ponds. 
Gomphus fraternus Say, Journ. Ac. Phila. 8, p. 16, 1839 ; Hagen, 
Syn. Nenr. N. Am., p. 104, 1861 ; Calvert, Ent. News, 12, p. 71, 1901 
(Differential Characters) ; Needham, Bull. 47 N. Y. State Mus., p. 451. 
1901 (Bibliography & Desc. of nymph). 
Abd. male 38, female 38—40 ; h. w. male 32, female 33. 
Male. — Olive, yellow, dark brown, and black. Face and occiput 
olive, vertex black. Thorax olive, marked with dark brown. A mid- 
dorsal stripe not reaching the anterior edge of the thorax. A wide 
antehumeral and humeral connected at their lower edge, sometimes 
also above. Abdomen black, 1 — 7 with a mid-dorsal stripe, broad on 
1 — 2, lanceolate on 3 — 7, interrupted at the apex of each segment, olive. 
The stripe ends with a triangular spot on the base of 8, rarely on 9, 
Sides yellow or yellowish green on 1 — 2 and 8 — 9, basal spots on 3 — 7. 
Appendages black. Segment 10 is about one-third the length of 9. 
Legs black, fore femora with some olive beneath. Costa of wings 
olive, pterostigma brown. 
Female. — Similar. More yellow on the abdomen. The legs black. 
