38 



MISC. PUBLICATION 318, U. S. DEPT. OF AGRICULTURE 



Figure 96. — Damsel fly 



winter as nymphs in water, particularly in ponds and lakes, and may 

 be considered of some value as enemies of flies and mosquitoes and as 

 fish food. The life changes are incomplete. The species shown here 

 is the 10-spotted dragonfly (Libellula pulchella). Its body is about 

 2 inches long and its wing expanse about ?>y 2 inches. This insect 

 belong to the order Odonata. 



Damsel flies. — There is another group of the Odonata called 

 damsel flies. They have long, narrow bodies with shiny wings that 



taper rather sharply to the point where 

 they are attached to the body. When at 

 rest these wings are folded rather close to 

 the body. These insects have chewing 

 mouth parts, and the adults catch small in- 

 sects from the air during flight. The 

 nymphs feed on small insects and other 

 aquatic animals, and winter usually in 

 small streams. The life changes of the 

 damsel fly are incomplete. These insects 

 are of some importance, as are the dragon- 

 flies, and for the same reasons. The species 

 shown here is the black- winged damsel fly 

 (Agrion macidatum) . It has a body about 

 1% inches long and a wing expanse of 2% inches. In this species the 

 wings are shiny black and the body metallic green with black on the 

 thorax. 



Termites. — In recent years we have been hearing more and more 

 about a little insect pest that has caused destruction to frame build- 

 ings. Many people call this insect the white ant. It 

 is really not an ant but a termite, which belongs to 

 the order Isoptera. Termites differ from ants in that 

 the body is of fairly uniform width throughout its 

 entire length, whereas the body of the ant appears 

 pinched in the middle to almost a thread. Termite 

 wings are about twice as long as the body, whereas 

 the wings of the ant are about as long as the body. 

 The members of this family are social and live in 

 colonies as honeybees do. Each species has a number 

 of different forms or castes within the colony. Most 

 people make the acquaintance of termites during 

 swarming season, at which time they come out in 

 great droves from around the floor or foundation of 

 an infested house. Termites during the swarming 

 season have four rather large wings, loosely attached to the body. 

 The workers of this group of insects are the ones that cause damage 

 by chewing the wooden parts of houses, but they also work on a 

 great many plant or animal products. Most species of termites work 

 under cover and must have contact with soil moisture. In nature, 

 termites can be found feeding almost any place where there is dead 

 wood on or in the ground. The species shown here is ReticuU- 

 terme\s flavipes, and this worker is about one-fourth of an inch 

 long. 



Earwigs. — Collectors often come across insects with hooklike ap- 

 pendages on the hind portion of the body. These, no doubt, are 

 earwigs, which belong to the order Dermaptera. They have chewing 



Figure 97. — Ter- 

 mite. 



