404 INTEENAL PARASITES. 



these parasites in the intestines and blood-vessels, induce loss of 

 condition, general debility, unthriftness of the coat, and some- 

 limes a dropsical swelling under the belly. The treatment appro- 

 priate to the removal of these parasites from the intestines is 

 similar to that for round worms (p. 400), namely, by tartar emetic 

 and sulphate of iron, followed by a purgative, or we may try 

 thymol (p. 406). 



4. SCLEROSTOMA TETRACANTHUM (Strongylus tetracan- 

 thus) somewhat resembles the palisade worm in appearance. The 

 fore part of its cylindrical body tapers towards the head, which is 

 truncated (cut short off). The mouth is circular, and is provided 

 with four prominent spines (or suckers) ; hence its name. The 

 mouth has two other suckers (or papillae), but they are compara- 

 tively short. This worm uses its suckers to attach itself to the 

 mucous membrane of the intestine. It varies from a third to three- 

 quarters of an inch in length, and is white j although it usually 

 appears to be of a blood-red colour during life, by reason of the 

 blood which is generally contained in it. Hence, it is often called 

 " the red worm." 



This parasite and the palisade worm are found more or less 

 frequently all over the world. I learn from Veterinary-Surgeon 

 Desmond that they are found in Australia, only on pastures which 

 have been for a long time under cultivation ; that lucerne pad- 

 docks give the greatest number of cases ; and that these parasites 

 have been imported into the Australasian colonies. The s. tetra- 

 canthus and s. armatus are almost always associated together in 

 their attacks on horses. 



Its fa\^ourite haunt is marshy land, like the Cambridgeshire fens, 

 where it is a constant resident, according to Mr. H. C, Wilkie, 

 F.R.C.V.S. ("Journal of Comp. Path." March, 1896). Mr. W. 

 Shipley, jun., F.R.C.V.S., states: — "As far as my experience goes, 

 I believe certain pastures are infested with these worms, and 

 colts turned on them invariably get them. As a rule, they are 

 low-lying, indifferent marshes. I have not, however, satisfied my- 

 self as to their existence on some old heavily-wooded parks and 

 pastures, but I always look to old, poor marsh land. It is certain 

 that marshes on which husk is known to be prevalent are also 

 infested with these worms. I have clients who invariably lose a 

 colt or more from these worms, while their neighbours never have 

 a case" (The "Veterinarian," March, 1896). Husk is a form of 

 bronchitis which frequently attacks sheep, and which is caused 

 by the entrance into the windpipe of worms (strongyli) that are 

 closely related to the palisade worm and the " red worm." It 

 is therefore evident that gi^ound which harbours the parasites of 



