124 BOARD OF AGRICULTURE. 
water, to which may be added a small amount of salt, oil of 
anise-seed, or assafcetida. Sometimes decoctions of quassia, 
worm-wood, or southern-wood (Artemisia abrotanum) are 
used for this purpose, with good results. To these a portion 
of olive-oil may be added. But any remedy that may be em- 
ployed must be repeated as often as once every three or four 
days for at least three weeks, in order to destroy the young 
ones as fast as they develop. An application of mercurial 
ointment to the parts about the anus is recommended to pre- 
vent the migrations of the parasites and the uncomfortable 
itching sensations that they thus produce. 
The common Round-worm of Man (Ascaris lumbricoides 
Linn.). 
‘This species is well known as a parasite of the human in- 
testine, especially in children, though often found in persons 
of all ages. The round-worm of cattle is generally regarded 
as the same species. 
These worms are round and smooth, tapering to both ends, 
with a tough, elastic skin. The mouth is situated at the more 
pointed end, and is provided with three prominent papille, or 
fleshy lobes. The male grows to the length of six inches, 
and has the posterior end curved and provided with two 
slender spicules. The female is much larger, sometimes be- 
coming twelve or fourteen inches long and one-fourth of an 
inch in diameter; the female genital orifice is in advance of 
the middle of the body. 
Development. 
The females produce great numbers of minute eggs, which 
are provided with thick, rough shells. The eggs are dis- 
charged and pass from the human intestine before the 
development of the embryos commences. If kept 
in water the embryos go on developing slowly and 
gradually, the whole process requiring from six months 
to nearly a year. The fully developed embryos are 
round and slender, about +35 of an inch long, with 
an obtuse head and an acute tail. They have not been ob- 
served to quit the eggs of their own accord, but may live for 
at least a year withinPive vew-sherpafter they attain their full 
