THE BLUE-BOTTLE FLY. 89 
eamel-hair brush lay them out. Examine with the 
inch objective. The stomach and the intestine as far 
as the malpighian tubes are coated with longitudinal 
and circular bands of muscles. The malpighian 
tubes unite to open into the intestine by two ducts 
opposite one another. The tubes have numerous 
constrictions. A short distance below the malpighian 
ducts, the intestine is constricted ; it then swells out 
into a pyriform sac, and is again constricted. It is 
then largely dilated, and contracts to the anus. Upon 
this dilatation are situated the four rectal papilla, 
the function of which is unknown. These papille 
are conical, and folded over the rectum; they are 
hollow, and at the end of each are a number of small 
projections, bearing bunches of sete on the tops. 
8. Reproductive organs.—In the female, the ovaries con- 
sist of a number of tubular follicles, arranged side by 
side, opening into the expanded end of the oviducts. 
These oviducts unite into one, which receives at its 
termination the ducts of two cylindrical, semi-trans- 
parent albwmen glands. Just where the albumen 
glands open into the oviduct, the spermathece branch 
off. These are three in number, each consisting of a 
dark brown, or black, chitinous capsule situated on a 
long tube. A little below the openings of the sper- 
mathecee, the oviduct swells out into a vagina. In 
the male, the testes are two pyriform bodies, sur- 
rounced by a layer of glandular cells. The ducts unite 
together to form a vas deferens. Just where they 
meet, two cylindrical albumen glands also open into 
the vas deferens. On the vas deferens is seated a 
chitinous capsule, surrounded by muscles. This is 
the eyaculatory organ. 
