ANNULOSA: INSECTA. 



261 



descend suddenly upon a district, and in a few hours destroy 

 all crops, and devour the leaves of all the trees, migrating as 

 suddenly as they came, so soon as the ground is utterly bare. 



Fig. 89. — Migratory Locust {^Acrydium tnigratorinm). 



Order VI. Neuroptera. — Mouth usually masticatory; 

 wings four in number, all membranous, generally nearly equal 

 in size, traversed by numerous delicate nervures, having a 

 longitudinal and transverse 

 direction, and giving them a 

 reticulated, lace-like aspect. 

 Metamorphosis generally in- 

 complete, rarely complete.- 

 The larva active, hexapod, 

 rarely with pro-legs. 



This order includes the 

 Dragon - flies (Libellulidce), 

 Caddis - flies (JPhryganeida) 

 May-flies (Efhemeridce)* the 

 Ant - lion {Myrmeleo), Ter- 

 mites, &c. The last of these 

 — namely, the Teimites or 

 White Ants — are social, and 

 live in communities, and their 

 habits are so singular that a 

 short description of them will 

 not be out of place here.' They are mostly inhabitants of hot 

 countries, where they are commonly known as " White Ants ; " 

 but it must be borne in mind that they have nothing to do 

 with the insects commonly called = Ants, which belong, indeed, 

 to a different order (Hymenopterd)^ The following account is 



* By some the Dragon-flies (LibelluUdce], the May-flies (Ephemeridte), 

 and the Termites (Termitidis), are placed in the Orihoptera, under the' 

 common name ai PsAido-neunpt&ra ; whilst the C3&&%-9iKs{Phryganeid<je'i 

 form a separate order under the name of Trichoftefa, 



Fig. 90. — Neuroptera. Aphis- lion {^Hetn^ 

 robiidce\ imago, larva, aild eggs. 



