INTRODUCTION. 
7 
for suction, as in the Lepidoptera (butterflies and 
moths), Rliyncota (bugs and their allies), and Diptera , 
or two-winged 
insects, as flies 
and gnats. In 
the Mandibulate 
or biting insects 
the mouth con¬ 
sists of no less 
than six separate 
parts, viz., (1) a 
pair of horny 
curved jaws 
(mandibles) 
often furnished 
with strong 
sharp teeth; 
(2) another pair of jaws (maxillae) lying beneath the 
mandibles, generally made up of four parts, formed for 
chewing and conveying the bitten off pieces of food to 
the mouth; these organs generally bear one or two 
pairs of jointed appendages called palpi , “feelers;” 
(3) an upper up or labrirn attached to the lower part 
of the front of the head, and (4) a lower lip or labium 
with a single pair of palpi. All these parts are readily 
made out, and I would advise the reader to examine the 
mouth of almost any beetle, so as to see clearly for 
himself the several organs; all that is required is a pair 
■of fine scissors, a lens, and a couple of strong needles 
set in wooden handles. 
The labium is generally composed of two or more 
■distinct parts, a basal portion called the chin or mentum , 
Mouth of Caterpillar of Hawk-moth (magnified). 
a, Upper lip. b , Mandibles, c , Maxillae, d, Lower 
lip. e, Antennae. /, Eyes. 
