Dragon-flies and Damsel-flies 
9 1 
clear-winged true damsel-flies. Most of them are small, and many keep 
so closely in low herbage or shrubby woodland that they attract little atten¬ 
tion. A few of the longer-bodied and longer-winged forms, however, fly 
in the open along the stream-banks or over the ponds. Some are strikingly 
varied with black and orange or yellow, and all, whether brightly colored 
or dull, are graceful and charming. There are at least a dozen genera of 
Agrionids in this country, comprising about seventy-five species, but their 
classification is too difficult to be undertaken by general students. Damsel- 
flies deposit their eggs in the tissue of aquatic plants by cutting slits in the 
stems with their sharp ovipositor. The nymphs are slender and elongate, 
and can readily be known by the three caudal leaf-like tracheal gills. The 
nymph stage of these forms is much shorter than with the true dragon-flies, 
lasting usually probably but a few weeks, or at most two or three months. 
When ready to transform the nymphs crawl out of the water and into the 
low herbage on the stream or pond bank. I have seen scores of freshly 
emerged damsel-flies rising from a few square yards of tall grass near a pond, 
although it required close search to discover the nymphs, so well concealed 
were they in the dense tangle. 
SUBORDER ANISOPTERA. 
Key to Families (Imagoes). 
Antecubitals of the first and second rows mostly meeting each other; triangle of 
fore wings with long axis at right angles to the length of the wings, triangle 
of hind wing with long axis in direction of the length of the wing. 
Libellulid,e. 
Antecubitals of the first and second rows not meeting (or running into each other) 
except the first and another thick one; triangles of fore and hind wings of 
similar shape (Fig. 121). 
Eyes meeting above on middle line of head; abdomen with lateral ridges. 
/Eschnid^e. 
Eyes just touching at a single point or barely apart; abdomen without lateral 
ridges. Cordulegasterid^e. 
Eyes distinctly separated; abdomen without lateral ridges. Gomphid^e. 
Key to Families (Nymphs). 
Under-lip (labium) flat, not concealing most of the face, with jaw-like or oblong 
side pieces (lateral lobes). 
Antennae 7-segmented, tarsi 3-segmented, climbing nymphs. .^Eschnid^e. 
Antennae 4-segmented, the fourth segment rudimentary; fore tarsi 2-seg¬ 
mented; burrowing nymphs. Gomphid^e. 
Under-lip (labium) spoon-shaped, covering most of the face, when closed, with nearly 
triangular side pieces (lateral lobes). 
Two stout teeth with a notch between them on the middle lobe of the under¬ 
lip (labium). Cordulegasterid^e. 
A single median tooth on the middle lobe of the under-lip- Libellulid^e. 
