128 ANIMAL LIFE 
sharply edged, for cutting off bits of leaves and stems. 
Those which take only liquid food, as the butterflies and 
sucking-bugs, have their mouth parts modified to form a 
slender, hollow sucking beak or proboscis, which can be 
Fia. 61,—Acorns put into bark of tree 
by the Californian woodpecker 
(Melanerpes formicivorus bairdii). 
—From photograph, Stanford Uni- 
versity, California. 
thrust into a flower nectary, 
or into the green tissue of 
plants or the flesh of animals, 
to suck up nectar or plant sap 
or blood, depending on the 
special food habits of the in- 
sect. The honey-bee has a 
very -complicated equipment 
of mouth parts fitted for tak- 
ing either solid food like pol- 
len, or liquid food like the 
nectar of flowers. The mos- 
quito has a “bill” (Fig. 59) 
composed of six sharp, slender 
needles for piercing and lac- 
erating the flesh, and a long 
tubular under lip through 
which the blood can flow into 
the mouth. Some predaceous 
insects, as the praying-horse 
(Fig. 60), have their fore legs 
developed into formidable 
grasping organs for seizing and 
holding their prey. 
77. Adaptation for  self-de- 
fense.—For self-protection, car- 
nivorous animals use the same 
weapons to defend themselves 
which serve to secure their 
prey; but these as well as 
other animals may protect themselves in other fashions. 
Most of the hoofed animals are provided with horns, struc- 
