26 INSECTS 



are very peculiar in that each eye is di- water where the feet touch it. One would 



vided into an upper and lower part. Thus hardly expect it possible for an insect 



th^r insect has practically an upper and standing on the surface of water to get its 



lower pair, one adapted for sight at the feet dirty, yet the great care which they 



surface, and the other for vision under give to cleaning their feet clearly shows 



water. that dirt is of common occurrence, even 



The Whirligigs do not seem to be very there. The white or gray color on the 

 particular about their food, as they' will lower side of the body is due to the re- 

 accept both live and dead insects which flection of light from minute hairs which 

 fall into the water, and even under some cover the surface, and keep the insect dry 

 circumstances will feed upon plants, even when submerged. 

 When a beetle plunges beneath the sur- The marine relatives of our Striders 

 face, as he often does when frightened, have some curious habits. Some of them 

 he carries down a small bubble of air be- live out at sea, hundreds of miles from 

 tween the ends of his horny wings and land, where they are thought to feed upon 

 the tip of his body. On account of his the dead bodies of small animals. When 

 body being lighter than water it takes the surface of the sea is calm they glide in 

 some effort to dive, but none to rise to the colonies quickly over the surface, showing 

 surface. The two hind pairs of legs great skill in diving, but if the sea begins 

 which are used so much in swimming are to* become agitated they immediately dis- 

 very much flattened and plate like, mak- appear from the surface, 

 ing excellent paddles, as is shown by their Ferhaps the most remarkable habit 

 exceedingly rapid movements. which a surface insect has is that pos- 



The Water-skaters, or Striders, prefer sessed by some of the allies of the Skaters,, 



quiet waters, as do the Whirligigs, but do which not only swim in the water, but 



not have the decided social disposition, actually run on the under side of the sur- 



shown in the latter to such a marked de- face film. It would be very interesting to- 



gree. These Skaters, on account of their know how such a habit was acquired, 



long legs and short bodies, are the "Daddy Another interesting group of insects 



long-legs" of the water. These character- are those which breathe air, as the surface 



istics and their habitat make them easy to film insects, yet seek their food below the 



recognize. They are nervous, active in- surface. These insects are compelled, on 



sects in their movements, jumping and account of their air-breathing habits, ta 



skimming about on the surface with but repeatedly visit the surface or communi- 



little show of grace and ease as compared cate in some way with a fresh supply of 



with the ordinary graceful curves of the air. 



whirligigs. Their food habits are very We have two families of the large-sized 

 similar to those of other surface insects, water beetles, common in our ponds and 

 that is, dead and dying insects found streams. The Predaceous water-beetles 

 floating on the water. But their method and the Water-scavenger beetles. These 

 of taking food is quite different from that are easily recognized, because in the for- 

 of the Whirligigs, because of the great mer, the antennae are thread-like and not 

 difference in the structure of their mouth enlarged at the tip. While the members 

 parts. The Whirligig, being a beetle, has of the Water-scavenger family have the 

 the typical biting mouth parts, while the antennae enlarged or club-shaped at the 

 Strider has a slender beak or proboscis, tip. The Predaceous water-beetles are 

 by means of which it sucks the juices often quite common under electric 

 from its prey, as do other bugs. The fore lights, where they have been at- 

 legs are used to seize the prey and bring it tracted by the intense light. Their 

 within reach of the beak. The middle and large size and clumsy movements, 

 hind pair are used for rowing over the when out of water, attract attention. But 

 surface, the latter pair, primarily, for when seen in water their skill as swim- 

 steerage, the fine hairs on the legs mak- mers is in striking contrast to their awk- 

 ing it possible, as mentioned before, to ward movements made on land. The hind 

 make use of the surface tension. Large legs are flattened and very powerful, the 

 dimples are formed on the surface of the surface being increased by a fringe of 



