LEECHES. 393 



of swallowing, and helps to dissolve sugar and starch. When it arrives in 

 the stomach, the gastric juice aids in dissolving the nitrogenous matter 

 (albumijji, etc.) contained in it ; and the muscular coat of the stomach churns 

 up the food and gradually pushes it into the small intestine, where it 

 meets the bile and pancreatic juice, which more or less complete the work 

 of digestion. The worm-like action of the muscular coat of the intestines 

 forces the food backwards, during which course, its digested portion becomes 

 more or less completely absorbed, until the residue enters the rectum in 

 the form of dung, and is finally expelled. 



Leeches {Hcsmopis). 



The leeches which suck the blood of horses, may be divided into 

 two classes: — (1.) Land leeches, which attach themselves to the 

 skin of the legs and adjacent parts of horses travelling through 

 their haunts ; and are consequently external parasites. (2.) Water 

 leeches (the horse-leech or hamojns sanguisuga, and other kinds) 

 not being able to penetrate the skin, attach themselves to the 

 mucous nlembrane, and, in this endeavour, enter the mouth or 

 nostrils of the horse when he is drinking or grazing in wet and leech- 

 infested pasture. They sometimes cling to the mucous membrane 

 of the eye. The horse-leech, which lives in water, generally 

 gains access to the mouth and nostrils, when young and when 

 not more than about a tenth of an inch in length. They usually 

 restrict their wanderings to the air and food passages in front 

 of the resjpective openings of the -windpipe (larynx) and gullet. 

 Their more or less numerous presence (over a hundred may be 

 found in one horse) causes loss of appetite, debility, wasting, and 

 even death by loss of blood or by obstruction to the breathing. 

 Besides these symptoms, their existence inside the horse may 

 be guessed at or ascertained by the animal bleeding at the nose, 

 by the foam of the mouth being Inixed with blood, and by the 

 parasites being seen on an examination of the nostrils and mouth 

 being made. 



Water leeches are found in various countries, and in great abun- 

 dance in Algiers. 



TREATMENT consists in removing the parasites, in sustaining 

 the strength by suitable food and tonics, and by performing 

 tracheotomy in the event of the leeches seriously interfering with 

 the breathing. Probably, the best way to dislodge them is to wet 

 them with a strong solution of salt and water, on being touched 

 with which they will loose their hold of the mucous membrane and 

 drop off. Apply the salt and water to those which are out of 

 reach of the hand by means of a piece of sponge firmly fixed to 

 the end of a sufficiently stiff rubber tube or other flexible stem ; 

 by drenching ; or by pouring the fluid down each of the nostrils. 

 The horse might be " coughed " (p. 289) now and then, so that he 



