OF INSECTS. 
180 
destined for the propagation of the species, may be 
said to have a general correspondence with those of 
the higher animals. They occupy the hinder part of 
the abdomen, and the external organs pass out by a 
distinct outlet, lying a little below the orifice of the 
alimentary canal. In the female, the following 
organs exist ; the ovaries , oviduct , and vagina ; 
besides various peculiar parts, as well as certain ex- 
terior appendages designed to convey the eggs in 
safety to their nidus, or to act as instruments of de- 
fence, termed ovipositor and sting. 
The ovaries are membranous tubes or bags in 
which the eggs are generated, and where they re- 
main till they acquire a considerable size. They 
are divided into two pretty equal portions, one lying 
on each side of the abdomen. Their shape is very 
variable, but most of them may be referred to the 
three following types of form. 1. Simple bags, 
containing the germs of the eggs. 2. Short ov- 
aries, thickly placed over the surface of a large 
bag-shaped common ovarium. 3. Long tubular 
ovaries, containing many eggs, resembling a necklace, 
either entirely free, or united by a loose cellular 
tissue. 
The oviduct is the canal which emanates from 
each half of the ovarium, and which both unite in the 
median line of the body, and form a common eva- 
cuating or ejaculatory duct. The length and capacity 
of these canals vary greatly. Sometimes they are 
supplied with glandular appendages, for the purpose 
of elaborating a glutinous matter, which forms a 
