Page:Insects - Their Ways and Means of Living.djvu/140



below the rnouth. Behind the rnandibles is a pair of maxdlae lB, Mx) of more cornplicated forrn, fitted rather for holding the food than for crushing it. Following the rnaxillae is a large under lip, or labium I Lb), having the

Ant - C Ht .- /I] An  Vent SoeGng C 6 7. Lençthwse se«t{on of ? grshopper, showng the enrl he pnn«p/ mtoEnl ornons, excep the resp{tory rachel system and the organs of repruction anus; .g.t, anoenna; Br, brain; Cr, op: Ht, heart: l.t, intestine: Malpighian tubules: Mt. mouth: Oe, oesophagus; SoeGn, suesopheal ganghon; ent, stomach (vent6culus); .VC, ventral nerve rd; , wings

structure of two rnaxi[lae united by their inner rnargins. A broad flap hangs downward befo're the rnouth to forrn an upper lip, or labrum (Lm). Between the rnouth ap- pendages and attached to the front of the Iabiurn there is a large rnedian lobe of the lower head wall behind the rnouth, known as the h.vpopharynx (Hphy). Insects feed, sorne on solid foods, others on [iquids, and their rnouth parts are rnodified accordingly. So it comes about that, according to their feeding habits, insects rnay be separated into two groups, which, like the fox and the stork, could not feed either at the table of the other. Those insects, such as the grasshoppers, the crickets, the beetles, and the caterpillars, that bite off pieces of food tissue and chew thern, have the rnandib[es and the other rnouth parts of the type described above. Insects that partake only of liquids, as do the plant lice, the cicadas, the rnoths, the butterflies, the rnosquitoes and other flies, have the

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