406 LIFE STORIES OF AUSTRALIAN INSECTS. 



body is shaped somewhat like the keel of a boat, 

 and this enables it to cut through the water. These 

 insects have to carry a supply of air down with 

 tliem, and they do so under their wing-covers; they 

 are lighter than the water, and have to hold on to 

 objects or swim in order to remain under the water. 

 They are very active insects, for they are pre- 

 daceous and are armed with the stout, short pierc- 

 ing beak, which can hurt one's finger in handling 

 them. They may fly from pond to pond; but they 

 can be kept in glass jars, with plenty of water 

 weeds, for months, Avithout needing any special 

 food, though they enjoy mosquito larvae. The 

 prothorax slightly overlaps the head, the hind 

 legs are the longest, and the back is keeled — these 

 points serve to distinguish them from the next 

 group, water boatmen. The common genus is 

 Enithares, 



WATER BOATMEN. FAMILY CORIXIDiE. 

 (Plate 53, Fig. 4.) 



The dorsal surface of these bugs is flat, and they 

 swim on the ventral side; this serves to distinguish 

 them from the back-swimmers. The front legs are 

 longest, and are clothed with fringes of hairs 

 (Plate 53, Fig. 4.) The water boatmen can obtain 

 their air by renewal with the air in the water, and 

 tlie whole body is covered with a fllm of air. One 

 can see these boatmen, kept for a time in jars of 

 water with water weeds, holding on to the plants 

 and gently moving the hind legs to promote circu- 



