52 THE FARM DOCTOR. 



nised as little, white, flaitened oblong objects progressing over 

 soil and vegetables by a worm-like movement, and depositing 

 an endless number of microscopic eggs, with which they are 

 literally filled. Some tape-worms are estimated to lay as many 

 as 25,000,000 eggs. Taken with the food or water into the 

 body of a suitable host these eggs open and set free an ovoid 

 six-hooked embryo, which bores its way through the tissues 

 until it reaches that organ or tissue which is the natural habitat 

 of its species in the young or larval state and there encysts 

 itself. It may survive indefinitely or even die in this situation, 

 or if its host is eaten by a carnivorous animal it may develop 

 in its bowels into a mature tape-worm and reproduce its species 

 as before. Fortunately nearly all the eggs perish from failing 

 to be taken into the body of a suitable animal in which they 

 can develop into the cystic form, or, this peril escaped, because 

 the first animal host is not devoured by the right species of 

 animal in which the young cystic worm can grow into its 

 mature tape-worm form. But from the enormous fecundity of 

 these tape-worms in eggs it is manifest that there may be 

 scarcely any limit to their increase when the different animals 

 which form their hosts in the cystic and mature condition 

 abound together in the same locality. 



STAGGERS. TURN-SICK. GID. STURDY. WATER-BRAIN IN 



LAMBS AND CALVES. 



The Tcenia Ccetmrus of the bowels of the dog, a tape-worm 

 of one to three feet long, has its cystic form — Ccetturns Cere- 

 hralis — in the brain and spinal cord of sheep and cattle, giving 

 rise to nervous disease, varying much in character according to 

 the exact site of the cyst. 



Symptoms. — Great nervousness and fear without apparent 

 cause, or dulness, stupor, and aberration of the senses, and 

 disorderly muscular movements. The sheep is found apart 

 from the flock with red eyes, dilated pupils, blindness, and 



