PERLID^E, OR STONE-FLIES. 157 



after their death, and their bodies are carted away as manure. 

 They take no food after their final change ; and as the propaga- 

 tion of the race is then their only object, they die almost as soon 

 as it has been performed, often in a few hours afttr they have 



PIG. 474. EPHKMEHA. 



quitted the water, the duration of their lives in their previous 

 conditions having been two or even three years. Like the Dra- 

 gon-flies, they have minute bristle-shaped antenna?, but the parts 

 of the mouth are rudimentary, and the extremity of the abdomen 

 is furnished with two or three long tails. 



739. The PERLID^:, or Stone-flies, resemble the preceding in 

 the possession of long bristles at the tail, and to a certain extent 

 in the imperfect nature of the buccal organs ; their larvae also 

 are aquatic, and respire by the agency of branchial organs at- 

 tached to the sides of the thorax and abdomen. But the long 

 tails of the Stone-flies are jointed appendages ; the antenna? are 

 long and filiform ; and the posterior wings, instead of being 

 smaller than the anterior pair, are considerably larger. The 

 common Stone-fly is found in plenty in most of our fresh waters, 

 and is much used as a bait by anglers, as is also its larva, which 

 closely resembles the perfect insect, and is commonly known as 

 the Water-cricket. An American species, described by the late 

 Mr. Newport, retains its branchial appendages even in the per- 

 fect state ; and the habits of this insect appear to be peculiarly 

 aquatic. 



740. The TERMITID^E, or White Ants> are terrestrial, active, 

 and carnivorous or omnivorous, during all their stages. They 

 are easily distinguished from the Dragon-flies and Day-flies by 

 their filiform antenna? ; and from the Stone-flies by the want of 



