62 
LIN'UEAN SYSTEM. 
Genus 16. Cemex. 
Jloslrum inflected: antenna longer than the thorax : zcings four, to. 
1J‘' 
crosswise; the upper ones coriaceous in the anterior part: back ^ 
thorax marginated: feet formed for running. {PI. 5. jig. 6, 7, 8.) 
The insects of this genus, whether as larva; or in the perfect st» 
feed for the most part on the juices of plants; some on the larva'* 
other animals: they have in general a very disagreeable smell. 
• 1 * 
larv® and pupae have six feet; they are active, and walk about like 1 ’ 
perfect insect: the former has no wings, the latter has the rudina' 1 
of them. A great number of species arc found in Britain. 
Sp. 1. Cimex Jectulunus. Without wings. 
Inhabits Europe. 
This insect (the bed-bug) is unhappily hut too well known, and 
an inhabitant of Europe prior to the Christian ara; at least it is i”“ 
tinned by Aristophanes arid other Greek writers. Southall say* it 
hardly known in London before 1070 ; hut there is good authority 11 
asserting that it was common enough there before the great lit® 
1666. It is a nocturnal animal, very fetid; seldom, though someth 1 ’® 
found with wings; easily killed when taken alive. Bugs are said to 
expelled in a variety ol ways, viz. by charcoal and oil of turpentine, 
soap, or hard pomatum. 
Genus 17. Aphis. 
Rostrum inflected: the vagina with five articulations and a single 
antenna: setaceous, longer than the thorax: wings four, erect, or no* 
fed formed for walking : the abdomen generally armed with two h° r 
(PI. 5. Jig. 9.) . 
The insects of this genus are small and defenceless; but very Il “ l 
ious animals, and most remarkable for Lite singularities in tbetrbisw 
and manners. They seldom appear before autumn, when the male** 
pregnate their females, which soon thereafter lay eggs or rather a sO ft . 
1 # 
capsule in which the young Aphides he already perfectly formed, , 
do not break their shell till t he following spring. When the' apl’^, 
• >ruf 
it is very remarkable that they are almost wholly females, with hs> rl 
a male to he seen during the whole spring and summer. Not'' 1 . 
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/ 
standing this, all these female Aphides without any communit' 1 ’ 1 ^ 
with a male are able to propagate their species, and seem to ha' (1 , 
ceived the genial influence not merely for themselves alone ht>* 
their posterity to the ninth generation. During the whole summf 
r d’ c 
are viviparous; and if a young Aply* be taken immediately up 01 ' J 
elusion from the mother, and kept apart, it will produce young; 
young, if also kept apart, will likewise produce, and so on, witho’’ 1 ^ 
presence of a male. Towards autumn, however, this singular f rt,c ^> 
cation begins to lose its wonderful effects; the Aphides cease tob r 
