92 NEUROPTERA. 



Germany they are used to feed the pigs. The Eev. A. E. Eaton 

 informs me that he believes that two species of Ephemeridce form 

 a portion of the so-called " Kungu Cake," manufactured by the 

 natives of South Africa, of gnats and probably any other insects 

 which can be obtained in sufficient abundance. The commonest 

 and best known species in England is Ephemera Vulgata, Linn., 

 the " Brown Drake " and " Green Drake " of anglers. One of the 

 most interesting of the foreign species is perhaps Oligoneuria 

 Ehenana, Imh., a white species, which appears in such vast numbers 

 on the Rhine after sunset as to resemble falling snowflakes. But 

 they live a very short time, and few or none survive till morning. 

 As already mentioned, fish are very fond of May-flies ; and in 

 some parts of the country the swarms which appear are called 

 " fishes' manna." The remains of several very large insects allied 

 to the Ephemeridce have lately been met with in the Devonian 

 formations of Europe and North America. 



PERLID^E. 



Four wings of equal size, folded in repose ; mouth imperfectly 

 developed ; antennae long ; abdomen frequently broad at the ex- 

 tremity, with a moderately long straight filament (much broader 

 and shorter than in the Ephemeridce) extending from each corner ; 

 larvae and pupae aquatic. 



The Perlidw, or Stone-flies, have considerable resemblance at 

 first sight to the Caddis-flies, from which their folded wings, 

 broad abdomen, and caudal setae will at once distinguish them. 

 Our British species are brown insects, of moderate size ; but some 

 of the foreign species are more brightly coloured ; thus the 

 insects belonging to the Australian genus Chloroperla, Newm., are 

 green. 



TERMITID^E. 



Social insects ; males and females with four large wings of 

 equal size (neuters wingless) ; mandibles well developed ; body 

 oblong and depressed. 



The Termites, or White Ants, have a great resemblance to ants 

 in their habits and economy, and are even more destructive in- 

 sects, as some species will hollow out any woodwork about a house 

 from the inside, never breaking through it, but leaving the surface 

 a mere shell, so that they may do irretrievable mischief without 

 their presence being even suspected. Fortunately no species has 



