Order ODONATA 
Dragonflies and damselflies 
Dragonflies and damselflies are relatively large and often beau- 
tifully colored insects. The adults have two pairs of elongate, 
membranous, many-veined wings of about equal size. The head 
and the compound eyes are large; the antennae are very small and 
bristle-like; and the abdomen is long and slender. Dragonflies may 
be up to 75 mm. long and they hold their wings in a horizontal 
position while at rest. Damselflies are usually somewhat smaller. 
Their wings are folded along the abdomen or are tilted up while 
at rest. Adults of both groups feed on various insects they capture 
while in flight. They are common and often abundant around slow 
streams and ponds. Dragonflies are particularly noticeable be- 
cause of their large size and rapid flight, back and forth, over the 
water. 
Dragonfly and damselfly nymphs are all aquatic and feed on 
various small aquatic organisms. Prey is captured through the 
use of a modified labrum containing two movable clawlike lobes 
at the tip. This device is held folded under the head when not 
in use and is about one-third as long as the body when fully ex- 
tended. The nymphs breathe by means of gills. In the dragonflies 
gills are in the rectum; in damselflies gills are three leaflike struc- 
tures at the end of the abdomen. Mature nymphs craw] out of the 
water and transform to the adult stage, usually on rocks or 
vegetation. 
Order ISOPTERA 
Termites 
The order Isoptera consists entirely of termites, one of the 
oldest and most primitive groups of insects. Termites are social 
insects and live in colonies. In all but a few species, there is a> 
definite caste system with each caste performing an essential 
function in the life of the colony. Termites feed on cellulose which 
they obtain from wood and other plants. Normally, cellulose is 
indigestible to animals, but termites have single-celled protozoan 
organisms within their digestive tracts (421) which convert it 
to simple digestible foods. Many species of fungi are associated 
with termites (342). Their influence on the activity of the insects 
is not completely understood, but certain species such as Lenzites 
trabea are known to produce an attractant (231). 
Only 40 species of termites are believed to be native to conti- 
nental United States. Of these, only 15 are known to occur in 
the eastern half of the country, exclusive of Texas (677). 
In addition to these native species, two introduced species, Cryt- 
otermes brevis (Walker) and Coptotermes formosanus Shiraki, 
also occur in the East. C. brevis may have been introduced into 
southern Florida from a nearby island. C. formosanus is believed 
to have been introduced into the Gulf Coast during World War II. 
Termites are small, flat, soft-bodied insects sometimes without 
eyes. The antennae are moniliform, and in the winged adults, the 
number of antennal segments varies from 12 to 25 or more. The 
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