50 
Nymphs one third to one half grown are transversely banded 
with brown across the head, across segments 4, 5, and 6 (some- 
times 7), and across 9 and 10. These bands disappear with 
subsequent molting, and the full-grown nymphs are of nearly 
a greenish color variously mottled with brown. 
Famiry GOMPHID AL. 
There is a marked ‘family resemblance” among the 
nymphs of each dragon-fly family, and this is quite as true of 
the present one as of any other. Its nymphs are all evident 
gomphids, even Hagenius, broad and flat as itis. Their most 
marked characteristic is the pair of thick, rough, four-jointed 
antenne. The flat labium is built on the same plan as that of 
the Agrionide and Al'schnide—the mentum, nearly truncate in 
front, bearing a powerful mandible-like pair of grasping arms, 
carrying on the outer side beyond the middle a large movable 
hook, the arms usually toothed within and ending in an 
incurved point. The domain of these nymphs, except Hagenius, 
is the muddy, sandy, or rocky bottom of various kinds of 
bodies of water, according to species. They live amongst 
fallen trash and sediment, burrowing shallowly along with the 
tip of the abdomen turned up so as to reach the water, thus 
enabling them to breathe while foraging in a stratum of great 
biological richness. Their colors are similar to the mud and 
sand in which they dwell, and are often obscured by a coating 
of mud. The flattened body and stout legs are well adapted 
for burrowing. The head is broad and more or less wedge- 
shaped, the antenne, laid close upon the labrum, forming the 
point of the wedge. The third antennal joint is much the 
largest; the fourth, a mere rudiment. The legs are stout, the 
two anterior pairs directed forward, their tibie armed at tip 
externally with more or less well-developed burrowing hooks. 
The hind legs are directed backward and used to push the body 
forward. The anterior and middle tarsi are two-jointed, not 
three-jointed as in other Odonata. The dorsal hooks and lat- 
eral spines are rather feebly developed. 
