93 
Dragon-flies and Damsel-flies 
water. The nymphs are slender, clean creatures, with smooth bodies pat¬ 
terned with green and brown, and very active, strong, and brave. They 
climb among green plants and roots or submerged driftwood along the border 
of open water or the edge of a current. The imagoes of this family can be 
recognized by the meeting of the eyes all along the top of the head. The 
wings are long, broad, and clear, and the body-colors are mostly bright blue 
and green. The family is represented in the United States by about twenty-five 
species, belonging to six genera. Anax junius, one of the commonest dragon¬ 
flies all over the United States, and found also from Alaska to Costa Rica, 
in China, Siberia, and in various islands of the Pacific, notably the Hawaiian 
group, is the most inveterate enemy that the mosquito has. It is conspicu¬ 
ously on the wing from early spring to 
late fall, flying from daylight to dark, 
and doing untold good by its Ceaseless 
warfare on the mosquito hosts. It 
can be recognized by its clear wings, 
large size (wings over two inches long), 
and bright-green thorax and head, the 
latter bearing on the upper front a 
round black spot surrounded by yellow, 
the yellow encircled by a dark-blue 
ring (Fig. 124a). A still larger member 
of this family is the great “hero” 
dragon-fly, Epiccschna heros, which is 
ance, but has‘'wm'gsT^^md^one-half inches long, and abdomen nearly three 
inches long. It has a black T spot on the upper face, instead of a round 
one. Another similar, widely distributed and common form is ALschna 
constricta, about the size of Anax junius , reddish brown marked with bright 
green, and with a black T spot on the upper front of face (Fig. 1246). The 
males have the abdomen marked with blue, with little or no green, while 
e females have but little blue or none at all. 
The members of the family Libellulidae are called “ skimmers.” They 
may be seen continually hovering over the surface of still water, or swiftly 
foraging over fields. Many of them have the wings strongly marked with 
large black or brown or milk-white blotches, and the abdomen is often 
covered with a whitish powder or “bloom.” They outnumber all the other 
true dragon-flies in point of species, and except for Anax junius , AEschna 
constricta , and perhaps the giant hero dragon-fly, include the most familiar 
and wide-spread members of the order. One of the best known and most 
beautiful of the skimmers is the pond-loving “ten-spot,” Libellula pulchella 
(Fig. 125), found all over the country. Each of its wings has a longitudinal 
basal blotch, a median blotch (at the nodus), and an apical blotch of black- 
Fig. 124a. Fig. 1246. 
Fig. 124a.—Top of head, showing charac¬ 
teristic mark in front of eyes, of Anax 
junius. (Enlarged.) 
Fig. 124&.—Top of head, showing charac¬ 
teristic mark in front of eyes, of JEschna 
constricta. (Enlarged.) 
like Anax junius in general appear- 
