50 ANIMAL ACTIVITIES. 
by the elongating of the maxillae of the caterpillar 
while it is in the pupa stage. These join by their 
edges to form a complete 
tube which the butterfly can 
coil or uncoil at will and in¬ 
sert in the flower on which 
it feeds. At the upper part 
of this proboscis there is a 
pump-like cavity provided 
with a valve. When this 
enlarges, the tip of the tube 
being inserted in the cup of 
honey, the liquid flows up 
the tube and fills the cavity. 
The cavity then contracts 
under the influence of the 
surrounding muscles. This 
causes a pressure which 
compels the valve to close 
and forces the honey for¬ 
ward into the stomach (Fig. 51). 
Depositing Eggs. At the adult period of its life, 
however, the butterfly is not a great eater. Its most 
important function, now, is reproduction, and for this 
purpose the female butterfly searches for the plant 
which will furnish suitable food for her young brood 
of caterpillars and deposits there her eggs, dying soon 
after the performance of this function. The eggs of 
the clover-butterfly are placed upon the under side of 
clover-leaves, one to each leaf. The eggs of the tent- 
caterpillar, so common on apple- and cherry-trees, are 
laid in large clusters glued to the branch of the tree 
by a gummy substance produced by the moth deposit¬ 
ing the eggs. In many cases the eggs of butterflies 
and moths show beautiful markings when studied with 
the aid of the microscope. 
Butterfly Enemies. If all the eggs of all the butter¬ 
flies and moths should be allowed to reach maturity 
Fig. 51.—Head of a Moth. 
a , upper lip; b , mandibles; 
c , proboscis; d, under lip; <?, 
antennae; f, eye. 
