On tape and cystic worms : with an introduction on the origin of intestinal worms / by Carl Theodor von Siebold ; translated by T.H. Huxley.

Siebold, C. Th. E. von (Carl Th. Ernst), 1804-1885.

Date:: 1857

Credit: On tape and cystic worms : with an introduction on the origin of intestinal worms / by Carl Theodor von Siebold ; translated by T.H. Huxley. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

10/101 (page 5)

$forth/or laid as eggs (that is to say, they emerge from the intes- tine of their parent's host), and seek an opportunity to enter into the intestine of some other creature. It is easy to convince oneself of this emigration of the young of the tape-worm, by examining the excrement of animals infested by them, at those times of the year at which they attain their sexual maturity. We then observe, that sometimes single joints, or connected series of joints, full of ova; sometimes immense masses of the ova, are passed with the faeces. The same thing holds good •with regard to the ova of the Distomata that infest the livers of our ruminating animals; their eggs, after they have been trans- ferred from the liver to the gall-ducts, being washed out with the bile into the intestine, and evacuated with the dung. These emigrations of the young of the intestinal worms benefit not only the creatures they infest, but themselves. There are many kinds of intestinal worms, in whose eggs the embryo is never hatched if they remain in the place where they have been laid. They must wander to some other place in order to develop their young, or to allow of the escape of the young already developed in them.^ These young must then either wait for, or seek, an animal to lodge in, having entered into which, they are capable of attaining sexual maturity. By such emigrations the infested animals are at the same time freed from guests, whose increase would be both troublesome and prejudicial. For example, what would happen if the millions of eggs that a single round-worm or tape-worm can produce, were to develop and generate their young in the same intestine in which they were laid ? Would not the intes- tine, after the young had attained their full growth, and brought forth others in their turn, become at last so choked up as to disable this part of the digestive apparatus, so that the whole organism of the unhappy animal must perish, together with his parasites ? In any case, the emigration and immigration of the young of the intestinal worms, is a very important though long Tinregarded part of the history of their propagation; and since ' Hence a tape-worra ^vhich has found its way into the intestine of an appropriate animal will attain its sexual maturity, but will not, properly speaking, multiply its kind there. Forthis reason, the tape-worm {Tania solium) infesting the human subject, which 13 common in Germany, France, [and England,] is commonly called the solitary worm, (Einsiedler-wurm, ver solitaire,) although the name is not a very fit one as It depends entirely on accident nhether only a single individual or a whole society of these worms shall enter the human intestine in the course of their wanderings$