BRANCH ARTHROPOD/1; CLASS IN SECT A : THE INSECTS 207 



thicker than the others, and the Dytiscidae or predaceous water- 

 beetles with two eyes and slender thread-like antennae. Try to 

 find Dytiscidae, large, oval, shining black beetles ; the larvae are 

 called water-tigers and are long, slim, active creatures with six legs 



FlG. 70. The forest tent-caterpillar moth, Clisiocampa disstria, in its 

 various stages; m, male moth; /", female moth; />, pupa; e, eggs (in a 

 ring) recently laid; g. eggs hatched; r, larva or caterpillar. Moths 

 and caterpillar are natural size, eggs and pupa slightly enlarged. 

 (Photograph by M. V. Slingerland. ) 



and slender curving jaws (see fig. 76). The June-beetles are the 

 heavy brown buzzing "June-bugs" and their larvae are the common 

 "white grubs "found underground in lawns and pastures. Have 

 live water-tigers and predaceous water-beetles in the aquarium. 

 Note their feeding and breathing. Compare the external structure 

 of the beetles with that of the other insects, noting especially the 

 biting mouth-parts, and their thickened horny fore wings serving 

 as covers for the folded membranous hind wings. 



