188 NATURE STUDY REVIEW [8:5— May, 19r> 



insect takes under water with it and enables it to stay under water 

 some time. It can leave the water and take to flight and is often 

 found around lights at night. The eggs, which are laid in or on 

 the submerged stems of water plants, hatch into little Back- 

 swimmers which are very much like the adults. Most Back- 

 swimmers feed on other water insects. To collect them, sweep 

 the vegetatioq growing in the edge of the water, all submerged 

 masses of tangled roots, around submerged logs, and in the water 

 under overhanging banks. Carry them home in a tin box con- 

 taining some wet water plants if the specimens are to be kept 

 alive; if not, kill them in a cyanide bottle. It is an easy matter 

 to keep them in an aquarium. Feed by dropping a few flies each 

 day into the water near them. Handle them carefully since they 

 have strong beaks and can make painful stings. 



The Water Scorpion (Fig. 13). 



If the young collector has sharp eyes he may find in the 

 quiet parts of streams and ponds, among the water weeds and 

 trash, a long slender insect, dirty brown in color and having two 

 long slender bristle-like breathing organs projecting from the tip 

 of the abdomen. The last two pairs of legs are long and used in 

 walking, while the front ones are used for the getting of food. 

 It may be seen clinging to some submerged stem with the two 

 long breathing organs reaching to the surface of the water. Thi.> 

 is the way it gets its air. The eggs are white oval objects with 

 two threads fastened to one end and are laid in the decaying stems 

 of water plants a few inches under water. The nymphs which 

 hatch from these are small but much like the parents except that 

 the breathing organs on the end of the abdomen are shorter. They 

 feed on water insects of many kinds, small fish, and even on one 

 another. Collect them by moving the dip net strongly back and 

 forth among the water plants. Carry them home in a tin box 

 containing a little wet water weed. Feed them in the aquarium 

 by putting living flies under the water near them. 



The Waterboatmen (Fig. 14). 



These insects appear in Spring soon after the ice melts on 

 streams and ponds. They may be found in running streams or in 

 quiet pools which contain water plants. They resemble the back- 

 swimmers in shape, but swim with the back up. All are small, 

 none being over -i inch long. They are oval, dark colored, and 

 have long, flattened hind legs which are used as oars in swimming. 

 They also come to the surface for air. carrying a supply below 

 with them, and are attracted to lights. They feed on smaller water 



