INTESTINAL WORMS. 
127 
Bound Worm (A scaris lumbricoides), so frequently found 
in children, is a familiar example. Professor Owen gives 
some curious details of the fertility of this species, which 
might well terrify us, but for the reflection with which he 
subsequently consoles us. “The ova are arranged in 
the ovarian and uterine tubes, like the flowers of the 
plantago, around a central stem or rachis. There are 
fifty in each circle — that is to say, you might count fifty 
ova in every transverse section of the tube. Now the 
thickness of each ovum is s ’„th of a line, so that, in the 
length of one lino, there are 500 wreaths of 50 eggs each, or 
25,000 eggs ! The length of each division, or horn of the 
uterus, is 16 feet or 2304 lines, which for the two horns 
give a length of 4608 lines. The eggs, however, gradually 
increase in size, so as to attain the thickness of soth of a 
line : we, therefore, have at the lower end of the horn sixty 
wreaths of ova in the extent of one line. The average 
number through the whole of the extraordinary extent of 
the tube may be taken at 14,000 ova in each line, which 
gives sixty-four millions of ova in the mature female Ascaris 
lumbricoides ! 
“ The embryo is not developed within the body in this 
species ; the ova may be discharged by millions, and most 
of them must, in largo cities, be carried into streams of 
water. An extremely small proportion is ever likely to 
be again introduced into tho alimentary canal of that 
species of animal which can afford it an appropriate habi- 
tat. The remainder of the germs doubtless servo as food 
to numerous minute inhabitants of the water; and the 
prolific Entozoa may thus serve these little creatures in 
the same relation, as the fruitful Cerealia in the vegetable 
