. Biology . Fig. 83.—Taenia solium. A, Entire tapeworm with proglottids; B, scolex withsucking discs and crown of hooks. (From Leuckart.) organic relation to the whole worm. Each segment has a com-plete set of reproductive organs which are quite as complex asthe reproductive organs of annelids or other animals of similargrade (see Fig. 84). When mature, the proglottids are de- 192 PARASITISM tached from the end of the tapeworm and are defecated with thefaeces of the host to the outside. Each proglottid has the powerto produce thousands of eggs which are fertilized when mature,. Fig. 84.—A sing
. Biology . Fig. 83.—Taenia solium. A, Entire tapeworm with proglottids; B, scolex withsucking discs and crown of hooks. (From Leuckart.) organic relation to the whole worm. Each segment has a com-plete set of reproductive organs which are quite as complex asthe reproductive organs of annelids or other animals of similargrade (see Fig. 84). When mature, the proglottids are de- 192 PARASITISM tached from the end of the tapeworm and are defecated with thefaeces of the host to the outside. Each proglottid has the powerto produce thousands of eggs which are fertilized when mature,. Fig. 84.—A single proglottid of Taenia solium enlarged to show the reproductiveorgans. (From Leuckart.) and stored up in the uterus of the proglottid, ready for develop-ment. When detached, a ripe proglottid then has thousands ofembryos, each capable of giving rise to a new tapeworm. Butthese are deposited with the faeces, and beforethey can develop into a new Taenia mustundergo partial development in the pig. Inone way or other, they find their way intothe food of a pig; the embryos are liberatedby action of the pigs digestive fluids, andwhen liberated make their way through thewalls of the digestive tract into the musclesof the pig. Here their development is ar-rested, and, as cysticercids or bladder-worms,they give rise to what is called measly pork eaten in an uncooked state is a spiralis, encysted in source of human infection. The bladder-muscle tissue. (From r j^1 J J. X xi- Hertwig after Boas.) worms are freed m the digestive tract, be-come attached as scolecids to
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