314 Veterinary Medicine. 



supervision of all dogs to prevent them from visiting abattoirs or 

 other places where they may eat the raw offal of animals. 3. The 

 medicinal treatment of all dogs passing segments of tape-worms, 

 especially of shepherd dogs employed on the pastures, and the 

 destruction of other dogs found on such pastures. 4. The 

 exclusion of dogs from the vicinity of wells or supplies of drink- 

 ing water for man or beast. 5. The sterilization as far as possi- 

 ble, by burning or boiling, of the dung of all dogs that suffer 

 from tape-worm and of all taken from kennels, and the destruc- 

 tion in the same way of all the contents of evacuated hydatids 

 and of offal containing such cysts. To these may be added : 

 6. The filtration or boiling of all drinking water and especially of 

 that drawn from shallow or imperfectly cemented wells in gravel- 

 ly or otherwise porous ground. 



Taenia Canina. T. Cucumerina. Melon-seed Tape- 

 worm. This is 3 to 12 or 14 inches long and 3 mm. broad in 

 mature segments. The head is elongated and terminated by a 

 very protractile club-shaped proboscis armed with four rows of 

 small recurved booklets like the thorns of a rose. When re- 

 tracted the proboscis is sunken in a median pit and surrounded by 

 the four sucking discs. The first segments are short and nearly 

 round or disc-shaped, the last are ellipsoidal like melon-seeds 

 (cucumis, hence the name). Genital organs double with two 

 pores, one on the centre of each lateral border, right and left, and 

 on a slight elevation. Ova globular, 37 ju, to 46 /a in diameter. 



Habitat. Abundant in the small intestine of the dog. 



Cryptocystis Trichodbctis. Cr. Pulecidbs. The cystic 

 form of the T. Canina is encysted in the dog louse (Trichodectes 

 lyatus) or in the dog flea (Pulex Serraticeps) , according as one 

 or other ma}' be the most convenient. The cyst was found in the 

 enlarged abdomen of the louse in 1869 by Melnikow, and only re- 

 cently in the body of the flea by Grassi. If a paste made by 

 crushing the ripe segment of the canina is placed on the skin of 

 the dog at a point infested by one of these skin parasites, a num- 

 ber of the latter soon show enormously distended abdomens, and 

 examination reveals the scolex in the centre of the swelling. In 

 seeking to rid himself of the vermin the dog swallows the infested 

 louse or flea, and the scolex develops in his intestine into the 

 Taenia Canina. 



