HEMIPTER A, OR BUGS

are Insect a invariably characterised by modification of mouth organs to form a suctorial, jointed proboscis, generally flexed so as to occupy a position on under side of body. The wings are four in number as a rule, and are external growths developed in succe ive moults from the hinder dorsal portions of the middle and posterior body-segments. They differ considerably in character in the two great the pairs varying in texture and folding flat on the back in the former, and in the latter covering the abdomen. The two sub-orders are further distinguished by the extent of the flexure of the head, this being much le in the Heter. than in the Homo. The young resemble the adult in general features, the transition from the juvenile to the adult being gradual. Amongst the most interesting forms, from an economic standpoint, are the Aphides or Plant Lice, which often swarm in incredible numbers over the host plant, and the scale insects or Mealy-bugs, which form small hard scales on fruit, twigs, etc. The A no pleura (Lice) are degenerate wingle members of this order.