RED WORMS. 405 



husk, is likely to be favourable to the growth and development 

 of palisade and red worms, and should therefore be avoided as 

 pasture lands by horse-owners. The same remark applies to the 

 parasites (Hulies) which often give rise to disease of the liver in 

 sheep. 



Mr. Shipley tells us that " yearlings are more liable to be affected 

 than adults ; in fact it is seen only rarely in five-year-olds and up- 

 wards. Moreover, in adults the effects are nothing like so dis- 

 astrous." 



The mode of attack of the sclerostoma tetracanthum is practi- 

 cally similar to that of the palisade worm, except that, as far as 

 we know, it does not get into the arteries. The embryos enter 

 the horse's system by means of the water he drinks, or the damp 

 forage he eats, and having arrived in the csecum or large colon, 

 they burrow through the mucous membrane of the intestine, and 

 each of them forms a cyst, in which it coils itself. It then under- 

 goes a stage of development, becomes mature, issues from its cyst, 

 attaches itself to the mucous membrane of the intestine (csecum or 

 large colon), and breeds ; the eggs being carried out in the dung. 

 The worms do not come to puberty until they leave their cysts. If 

 we open the csecum or large colon of a dead horse which is in- 

 fested with these parasites, and scrape the mucous membrane of 

 that part, we shall see on its surface, small dark spots, which 

 indicate the position of the cysts, and if we cut into one of them, 

 we shall find in it a coiled-up worm, which may be an embryo, or 

 an adult worm that is ready to quit its cyst and enter the intestine. 

 The foregoing account of the migrations of these parasites coim 

 cides with that given by Neumann, Friedberger and Frohner, 

 Cadeac and other authorities ; but some of the details of the sub- 

 ject have not yet been definitely settled. 



'•' I have had cases of this form of helminthiasis brought under 

 my notice as early as December, but as a rule I think they are more 

 numerous dming the months of January, February, and March. It 

 would seem that about this time the larvae, coiled up in the mucous 

 membrane of the csecum and large colon, are approaching matu- 

 rity. They have increased much in size, and many of them are 

 preparing to make a way through their epithelial covering, while 

 some are already free in the lumen of the bowel and have reached 

 their full development" (Wilkie). 



The principal symptoms, all of which are not necessarily present 

 at the same time, are as follows : — Dropsical swellings of the lower 

 surface of the belly, sheath and limbs; pale condition of the 

 mucous membranes; watery and more or less inflamed state of 

 the eyes ; bad smelling diarrhoea ; dulness ; debility ; emaciation ; 

 staring coat ; and the presence of the worms in the dung. " When 



