ANNULOSA : INSECTA. 



243 



ORDER IV. HEMIPTERA. Mouth suctorial, beak-shaped, 

 consisting of a jointed rostrum, composed of the elongated 



Fig. 84. Hemiptera. Bean Aphis (Aphis f aba), winged male and wingless female. 



labium, which forms a sheath for the bristle-shaped styliform 



mandibles and maxillae Eyes compound, usually with ocelli 



as well. Two pairs of wings. 

 The Hemiptera live upon the juices 



of plants or animals, which they are 



enabled to obtain by means of the 



suctorial rostrum. Amongst the more 



familiar examples of this order are 



the Plant-lice (Aphides, fig. 84), the 



Field-bug (Pentatoma), the Boat-fly 



(Notonectd], the Cochineal Insects 



(Coca), and the Cicadas. The order 



is divided into the following two 



sub-orders : 



Sub -order a. Homoptera. The 

 anterior pair of wings of the 

 same texture throughout 

 (membranous) ; the mouth 

 turned backwards, so that 

 the beak springs from the 

 back of the head. 

 Sub-order b. Heteroptera. An- 

 terior wings membranous near 

 their apices, but chitinous to- 

 wards the base (hemelytra). 

 The rostrum springing from 

 the front of the head. 

 ORDER V. ORTHOPTERA. Mouth 



masticatory; wings four; the anterior 



and in these cases there cannot be said to be any metamorphosis, since 

 the larvae differ from the adult only in size, in having fewer joints to the 

 antennas, and in having a smaller number of facets in each of the com- 

 pound eyes. 



