224 MEANS BY WHICH ANIMALS ADHERE 
an adhesive secretion is emitted. Some larve which 
are not supplied with prolegs (those of the Cocci- 
nelle, for example) have the inferior part of the tarsi 
of their perfect legs thickly covered with hair-like 
appendages, resembling in figure, and in the function 
they perform, those on the pulvilli of insects in the 
imago state; while others, altogether destitute of 
legs, emit a viscid mucus from both their extremi- 
ties, and by advancing and attaching each alter- 
nately are thus enabled to ascend smooth bodies 
with facility. 
The larvee of the Chrysomele, Coccinelle, and some 
other insects can protrude through an orifice at the 
extremity of the caudal or terminal segment of the 
abdomen a bundle of papillae, which, by a copious 
emission of mucus, gives them so secure an attach- 
ment to the objects on which they move, as readily 
to sustain their entire weight ; by assisting them occa- 
sionally in the act of progression it is also made to 
serve the purpose of an additional leg. Provided with 
a similar apparatus, the larva of the Glowworm (Lam- 
pyris noctiluca), though unable to ascend a vertical 
surface of glass, can adhere to one firmly by the appli- 
cation of this eorgan, which is composed of several 
branched membranous papillz included in a common 
envelope. They are extremely flexible and extensile ; 
and, either separately or collectively, can be pro- 
truded beyond the caudal segment or retracted 
within it at the pleasure of the animal. Their effici- 
