1908] 
Muttkoivski, Dragon Flies of Wisconsin. 
103 
Life Zone : Transition and Upper Austral. 
The species has been taken so near the boundary line of Illinois 
and Wisconsin, that it certainly can be expected in the State. 
Time and Habitat — May to July about ponds and quiet waters. 
DOROCORDULIA Needham, Bull. 47 N. Y. State Mus., p. 504, 1901 
(Discussion of Characters). 
The species of the present genus were separated from Cordulia 
chiefly because of dififerences in venation, such as open triangles 
and the presence of only two complete rows of cells beyond the 
triangles in the fore wings. Another point of difference is the 
entire (not furcate) inferior appendages of the male. The ima- 
goes are small, with metallic colors, graceful in flight, though less 
rapid than the preceding species, but quite as restive. Three 
species are known : 
1. Apex of abdomen (7 — 9) gradualh?^ and moderately dilated. ... 2 
Apex of abdomen (7 — 9) suddenly and spatulateW dilated .. libera 
2. Joints of abdomen yellowish lepida 
Joints of abdomen without yellow lintneri 
Dorocordulia libera Selys, Bull. Ac. Belg-. 31 (2), p. 263, 1871; 
Xeedham, Bnll. 47, N. Y. State Mus., p. 504, 1901 (Description of 
nymph) ; Williamson, Dragon-flies of Indiana, p. 314, 1900 (Description 
of imago). 
Abd. male 31, female 29 ; h. w. male 30, female 31. 
Male. — Color metallic green, obscured on the thorax by brown hair. 
Mouth yellow, face green. Abdomen green, sides of 1 — 2 black with 
brownish spots, the posterior segments black. Legs black. Wings 
hyaline, nervure, costa and stigma black. The base of the wings 
marked sparingly with brown or yellow. 
The female is similar. 
Life Zone : Transition. 
Wisconsin: Dane Co., June 1890; Door Co., Plum Island, July 
6, 1905. 
Time and Habitat — June and July about small lakes. 
CORDULIA Leach, Edin. Encycl. 9, 1815. 
The single species of this genus, C. shurteffi Scudder, is read- 
ily distinguished from its allies by the points specified in the table. 
In color and the few markings it resembles the preceding species 
D. libera, differing however, by having the abdomen more equal, 
not widely expanded at the apical segment. The species may be 
expected in Wisconsin, since it is found in Transitional regions. 
TETRAQONEURIA Hagen, Syn. Neur. N. Am., p. 140, 1861; Need- 
ham, Proc. U. S. Nat. Mus. 26, p. 723-726, 1903. 
Four species are referred to this geuns. 
1. Frons without a black T-spot above; if so, only faintly evident; 
triangle of hind wing generally crossed 2 
Frons with a black T-spot above distinct; triangle of hind wing 
generally free spinigera 
2. Hind wings with four antenodals 3 
Hind wings with five antenodals spinosa 
