DISEASES OF THE DIGESTIVE ORGANs. 17) 
the heart for its place of abode; another inhabits the arteries; a 
third, the kidney. Myriads of minute worms lie coiled up in the 
voluntary muscles or in the areolar tissue that conncts the flesh 
fibers. The gninea-worm and chigoe bore through the skin, and 
reside in the subajacent reticular membrane. Hydatids infest 
various parts of the body, but especially the liver and brain. A 
little fluke, in general appearance much like a minature flounder, 
lives, steeped in gall, in the biliary vessels. If you squeeze from 
the skin of your nose, what is vulgarly called a maggot (the contenta 
of one of the hair-pellicles), it is ten to one that you find in that 
small sebaceous cvlinder several animalcules, extremely minute, 
yet exhibiting, under the microscope, a curious and complicated 
structure. Even the eye has its living inmates; but it is in the 
alimentary tube that we are most infested with these vermin.” 
It is evident, from competent testimony, that these, as well as 
other kinds of parasites, are always more or less injurious; henca 
the same may be true as regards the bot in a horse’s stomach. The 
best authority we have for the origin and history of the bot is 
Bracy CLaRns, V. §., a selection from whose works is here in- 
troduced : 
“The Estrus Equi, or the Stomach Bot.— When the female has 
been impregnated, and the eggs sufficiently matured, she seeks 
among the horses a subject: for her purpose; and approaching him 
on the wing, she carries her body nearly upright in the air, and 
her tail, which is elevated or lengthened for the purpose, curved 
inward and upward. In this way she approaches the part where 
she designs to deposit the egg, and, suspending herself for a few 
seconds before it, suddenly darts upon it, and leaves the egg ad- 
hering to the hair. She hardly appears to settle, but merely 
touches the hair, with the egg held out on the projected point of 
the abdomen. The egg is made to adhere by means of a gluti- 
nous liquor secreted with it. She then leaves the horse at a smal] 
distance, and prepares a second egg, and, poising herself before the 
part, deposits it in the same way. The liquor dries, and the egg 
becomes firmly glued to the hair. This is repeated by these flies 
till four or five hundred eggs are sometimes placed on one horse. 
The skin of the horse is usually thrown into a tremulous motion 
or the touch of this insect, which merely arises from the very great 
irritability of the skin and cutaneous muscles at this season of the 
ear. occasioned by the heat and continual teasing cf the flies. till, 
