1908] 
MuttkowsKi, Dragon Flies of Wisconsin. 
93 
ambush. The species are widely distributed in all parts of the 
world. Genera found in the United States separate as follows : 
1. Subnodal sector simple 2 
Subnodal sector furcate near the apical third 4 
2. Triangle with several cross-veins, snpra-triangular space veined. 3 
Triangle with one cross-vein, siipra-triangiilar space free 
Gomphaeschna 
3. Wings broad, basal space with cross-veins Boyeria 
Wings narrow, basal space free Basiseschna 
4. Both sectors of the arculns arising not above its middle 5 
Both sectors of the arculus arising above its middle Anax 
5. One or two rows of cells between the subnodal and supplemen- 
tary sectors 6 
Three or more rows of cells between the subnodal and supple- 
mentary sectors ^^schna 
6. One row of cells between the subnodal and supplementary 
sectors Nasiaeschna 
Two rows of cells between the subnodal and supplementary^ 
sectors Epiasschna 
GOMPH/ESCHNA Selys, Trans. Ent. Soc. London, p. 413, 1871; 
Needham, Proc. U. S. Nat. Mus. 26, p. 718, 735, 737, 756, 762 (Venation). 
This genus is represented by a single species found within the 
United States. Little is known of the habits, since it has rarely 
been captured. The present genus with the two following forms 
a separate group, the chief distinction of which is the simple sub- 
nodal sector, as shown by the table. As distinctive from its allies 
it might be well to mention several other features besides those 
furnished in the table. A prominent feature is the presence of but 
a single cross-vein under the stigma ; also, the cubitus or the med- 
ian space, as it is sometimes called, contains only two cross-veins, 
while the related genera boast of three or more. As a further 
distinction the wings are furnished but sparingly with cells, and 
these large, not fine and resembling the closely knitted net-like 
meshes of the other Aeschninse. The single species, G. furcillata 
has been taken in the Upper Austral life Zone, but only in the 
more eastern states. The color of the species is brown, with the 
usual markings of the Aschninse. 
BOYERIA MacLachlan, Ann. Mag. Nat. Hist. 17 (6), p. 424, 1896; 
Needham, Proc. U. S. Nat. Mus. 26, pi 735-737, 1903 (Venation). 
Two species of this genus are known from the states. In com- 
mon with its nearest ally, Basicsschna, and distinctive from the 
preceding genus, Boyeria has several cross- vems under the pter- 
ostigma and three or more in the cubitus or median space. Both 
species of Boyeria occur in several life zones and are likely at any 
time to be discovered in the state. 
