BUG. 
163 
differ from the parent insect in no other respect 
than size and colour, being at first much paler 
than when more advanced in their growth; not 
arriving at their full size in less than about three 
months. They live entirely by suction, employ- 
ing for this purpose their sharp and fine trunk or 
proboscis, which is carried in a' strait direction 
beneath the breast. It is probable that this in- 
sect, like the Gnat and some others, at first infuses 
some quantity of irritating fluid into the wound it 
makes, before it sucks the blood of the animal it 
attacks, since the swelling which it causes is often 
very considerable, and attended with severe itch- 
ing. During the winter months these animals 
secrete themselves behind walls, wainscotting, or 
any neglected places, where they are capable of 
supporting the most intense frost without injury, 
and on the return of warm weather again emerge 
from their concealment. When confined in a box 
for any length of time they will often attack and 
destroy each otlier. It is affirmed by Scopoli, 
whose observations are, in general, distinguished 
by great accuracy, that this insect, in the Dutchy 
of Carniola, is, at certain seasons, furnished with 
wings, though apterous in other parts of Europe. 
Mr, Baker, in his work entitled The Microscope 
made easyT informs us that the Bug is one of the 
best subjects for exhibiting a microscopic view of 
the circulation of the blood. In the legs of 
small punices or Bugs (says this writer) the cir- 
culation is remarkably visible, together with an 
extraordinary vibration of the vessels, which I 
