70 
HALF HOURS WITH INSECTS. [Packard. 
which the current is continued with increasing rapidity by 
means of the pulsation of the pumping ventricle and the 
powerful peristaltic movement of the digestive tube.” Fig. 
55 shows this tube and adjacent parts of the head magnified 
one hundred and sixty times ; aa the end of the head ; bb the 
chitinous band, and c the base of the under lip ; d the under 
lip protruded, with the hooks ee ; and / the sucking tube, 
with a few blood disks passing through it. 
How a louse breathes is perhaps as practical a question 
as how it bites. All insects inhale air through a row of 
holes (stigmata) in the side of the body, which connect by a 
series of tubes (tracheae) within, ramifying throughout the 
body; no air is taken in through the mouth. Now grease 
and oil, when in contact with the sides of the body, tend to 
close up these breathing holes, and then the creature suffo¬ 
cates. Thus oil or pomatum is an antidote. A word to the 
wise is sufficient. 
Not only personally, but also indirectly, through those 
kinds which swarm on his domestic fowls and quadrupeds, 
is man affected by these creatures. Those species which 
live for the most part on birds have true jaw r s, enabling 
them to nibble and thus irritate the skin of their host. 
While we are upon this harassing theme we should not 
pass over that kindred subject the bed-bug. This insect, 
with a body so flat that an ordinary punch with the thumb 
only seems to tickle it, seems preordained for a life in cracks 
and crannies. First noticed in literature by Aristotle, 
it was also mentioned by Dioscorides and Pliny. It was 
first met with in Germany in the eleventh or twelfth century, 
and was mentioned as an English insect by Mouffet in 1503. 
It is possible that its original haunt W'as the nests of doves 
and swallows; and the most effective way, should it seem 
desirable to ensure an abundant harvest of these pests, is to 
keep a number of these birds about our houses. Whether it 
actually lives under the feathers of doves or not could be 
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