482 PREVENTION OF VERMlOEOUS DISEASES. 



should be carefully carried out, instead of throwing the same to 

 dogs, &c. 



The ova and embryos that form the hydatid stages or cysts are 

 obtained in a great number of cases from polluted drinking-water. 

 The eggs passed out of the sexual tapeworm, and thus out of its 

 host, often are left upon the ground, and get carried by rain to 

 runnels, ditches, dykes, and rivers. Yet many are taken oft' the 

 ground direct by herbivorous animals. Sometimes whole proglottides 

 voided out in the dung are eaten, and then the aiiimal is invaded, 

 if it be the proper host, with hundreds of small cysts, as seen in 

 Cysticercxis cellulosoe in pigs. We must bear in mind that we cannot 

 get rid of these cysts when once they have taken up their rendezvous 

 in the organs, except in the isolated case of Cxnwus eerebralis, which 

 may sometimes, if a single cyst only exists, be extracted from the 

 sheep's brain by trephining. It is therefore very -essential to 

 prevent the ova of cestodes from entering an animal. To do this 

 we must endeavour to keep our stock, and especially our dogs, free 

 from these worms (and other parasites). When they are noticed by 

 such symptoms as thinness, capricious appetite, irritation in the 

 lumbar regions, and the presence of proglottides in the excreta, the 

 patient should be shut up, well dosed, and all excrement, with the 

 expelled ova, proglottides, and scolices, burnt. We must bear in mind 

 that as long as the scolex remains the cestode can continue to grow, 

 thus necessitating the certain expulsion of this budding area. 



In regard to tseuicides, great numbers of substances have been 

 experimented with, and many are more or less successful. Before 

 dosing, the patient should be given no solid food for at least twelve 

 hours previously, but a small quantity of soft food only. A mild 

 dose of castor-oil should also be given beforehand. The most certain 

 drugs are areca-nut, male fern, calomel, pomegranate bark, and 

 sulphuret of calcium. Perhaps the best is a mixture of areca-nut 

 and male shield-fern powders in the proportion of 2 grains of areca- 

 nut to every pound- weight of the dog, with 15 minims (drops) of 

 male shield-fern extract. This tsenifuge should be given in sweet 

 milk, and is best followed next morning with a mild dose of castor- 

 oil. As a rule, two doses of the powders are necessary. ^Ethereal ex- 

 tracts of male shield-fern in 2-grain to 6-grain doses also brings away 

 the worms. Similar drugs may be used for sheep and poultry in 

 varying doses. But for sheep, kamala in 10-grain doses has met with 

 most success. In poultry I have obtained excellent results with the 

 extract of male fern, about 10 drops administered in salad-oil. 



