672 



THE NATURE BOOK 



tail-like organs, which, when placed to- 

 gether, form a breathing tube. The 

 rostrum or beak of the Water Scorpion 

 is composed of three joints, and contains 

 four sharp-pointed bristles, altogether a 



very com- 

 pli cat ed 

 apparatus, 

 and c a p- 

 able of in- 

 flicting a 

 very pain- 

 ful wound. 

 At the ap- 

 proach of 

 danger the 

 Water Scor- 

 pion can 

 mo\-e with 

 consider- 

 able rapid- 

 i t y, and 

 quickly re- 

 veals its 

 true character. Under normal conditions, 

 however, it creeps slowly about amongst 

 the decaving lea\-es at the bottom of the 

 pond, suddenly darting upon its prey, 

 from which it sucks the blood by means 

 of its short, complex beak. 



A close and interesting relation of the 

 Pond- Skater and the Water Scoi-pion is 



the Water 

 ^ Boatman 



{Nolo necta 

 g I a u c a), 

 which is gen- 

 erally to be 

 found in the 

 same ponds 

 and s 1 o w- 



THE WATER SCORPION. 



THE WATER BOATMAN. 



m O V 1 n g 

 streams. This 

 insect, as its 

 popular name 

 vaguely sug- 

 gests, has its 

 body shaped 

 something 

 hke a boat, 

 convex above like the keel, flat below, 

 with a large head and very large eyes. 

 The front and second pair of its legs 

 are short, but the hind pair are almost 

 twice as long, are furnished with long 

 hairs, resemble oars, and are used by 



the insect to propel itself through the 

 water. It is a most bloodthirsty and 

 fearless insect ; it attacks other msects 

 much bigger, and apparently stronger, 

 than itself, and also pre3-s upon its own 

 species. 



Of very great interest is the life-history 

 of the Gnats or Mosquitoes, not only be- 

 cause the early stages are passed in ponds, 

 ditches, and shallow pools, but because 

 some species in the adult stage of their 

 existence are the transmitting agents of 

 certain diseases — malaria and j-ellow fever 

 among them — to man. The female Mos- 



THE GNAT LARVA RISES TAIL FIRST 

 TO THE SURFACE. 



quito or Gnat lays her eggs in boat or 

 raft shaped masses upon the surface of 

 the pond, and from these eggs come 

 forth quaint -looking little creatures with 

 large heads adorned witli tufts of 

 bristles, and with fairly long slender 

 bodies terminating in what looks somewhat 

 like a double tail. They move through 

 tlie water with rather a jerky, wrig- 

 gling motion, and from time to time 

 rise to the surface tail first, and stick 

 the curious tail-hke process which is 

 attached at right -angles to the general 

 outhne of the body, and is called the 

 syphon-tube, out of the water to take in 



