HEMIPTERA. I09 



The mandibles and the maxillae are formed into an effect- 

 ive piercing and sucking organ called the beak; and this 

 is enclosed by the labium, which is in this order formed of 

 two pieces, grooved on their inner edges, and fitting to- 

 gether around the stylets so as to form a tube or suction 

 pump, by which the sap of the plant or the blood of the 

 animal is pumped into the greedy maw of the blood-thirsty 

 bug. (Fig. 47.) One predatory member of the order is 

 fond of the green cabbage worm, and may be watched 

 while it energetically pumps away the life blood of the 

 unlucky worm, working the sharp stylets up and down 

 inside the hole made by the labium. 



Unlike the beetles, the hemipters pass through no 

 pronounced changes on the way to adult size. Except the 

 males of the scale insects, all of the order have incomplete 

 metamorphosis, passing through the egg and the extended 

 larval stage, which merges into the adult form by means 

 of repeated moultings while the insect is eating and grow- 

 ing. The insect just hatched from the egg is a tiny bug, 

 resembling its parents in form and food habits; but it 

 has no wings, and its colors are often different from the 

 adult colors. 



Having the same sort of mouth parts, the young bugs 

 have the same food preferences as do the adults, and hence 

 the young are to be sought in the same places as the adults. 

 The egg-laying process usually occupies some days ; hence 

 in any brood are to be found young bugs in many stages 

 of development; from those just hatched, tiny, wingless 

 individuals, to the winged adult, all sucking away at the 

 pumpkin or cabbage leaf. Usually the predatory insect 

 insists upon the right of discovery, and preempts its 

 victim to the exclusion of other insects — a useful habit, 

 as it rids us of many more injurious insects. 



