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bya cross-vein connecting it with the stem of the 
second anal without an evident intervening fork. 
dd. Basilar space (between the arculus and base of 
wing) crossed by 2-6 cross-velns; supratrian- 
gular space with cross-veins; male anal triangle 
3—5-celled. Il. Boyeria. 
d. Basilar space free or with a single cross-vein. 
ee. Supratriangular space with cross-veins; 2 or 3 
rows of cells between the radial sector and 
the supplementary sector below it; male anal 
triangle 2-celled. IV. Basieschna. 
e. Supratriangular space free from cross-veins, one 
row of cells between the radial and supple- 
mentary sectors, male anal triangle l- or 2- 
celled. Gompheschna. 
a. Radial sector forked or branched beyond its middle, 
supplementary sector diverging from it until three 
or more rows of cells intervene between the supple- 
mentary and the basal part of the posterior branch, 
beyond which the supplementary curves rather rap- 
idly upward toward the branch; anal loop much as 
in bb, the first anal reaching more than half way 
(usually about two thirds) across the bottom of the 
loop, and connected with the second anal by a short 
oblique cross-vein, so that the anal loop appears 
4-sided with a truncated inner hind angle; triangles 
of both wings 4- or 5-celled, inner side almost always 
recelving a cross-vein. V. A’schna. 
A, Upper part of arculus much shorter than its lower part, its 
upper sector arising about midway between the lower 
sector and the median vein above; radial sector emitting 
a number of oblique branchlets on its posterior side, but 
not regularly forked; anal loop apparently 4-sided, the 
first anal extending nearly across the bottom of the loop, 
the connecting cross-vein very small and inconspicuous, 
usually meeting the second anal at about a right angle. 
VI. Anaz. 
