THE ANATOMY OF THE HORSE. 39 



Is the large pari, and is placed in front; the neck being ta 

 the back part of the bladder. This is where the urine or water 

 passes out of the bladder. The bladder is made up of three coats, 

 somewhat similar to that of the bowels. The serous coat is just 

 a continuation of the serous coat found in the belly cavity lining 

 the bowels. The inside of the bladder is lined with mucous 

 membrane similar to that of the bowels, and when the bladder is 

 empty this is all thrown into folds. Another coat is found, 

 between the two membranes above mentioned, called the muscular 

 coat, and is made up of muscular fibres. Its action is when the 

 bladder is full and presses on the nerves of the coat, these nerves 

 causing the fibres in the coat to contract, thus contracting- the 

 bladder, forcing the urine out. The bladder is held to its place by 

 ligaments attached to the wall of the pelvic cavity, and above the 

 bladder is found the rectum. The bladder in the horse rests on 

 the floor of the pelvic cavity. The position of the bladder in the 

 mare differs from that of the horse. Instead of the rectum or 

 back bowel being immediately above it, as it is in the horse, the 

 womb is found just above the bladder or between it and 

 the rectum. The use of the bladder is to act as a reservoir to 

 store up the water until the bladder is full ; when it is full it 

 presses on the walls and nerves, giving a peculiar sensation to 

 these parts, and causing the walls of the bladder to contract 

 forcing the water into a tube which carries it from the body; this 

 tube is called the urethra. The neck of the bladder is simply an 

 opening at the back part of the bladder, and is guarded by a 

 valve which prevents the urine from dribbling out except when 

 the animal is passing its water. 



The Urethra is the tube which carries the water from tht 

 bladder out of the body, and is situated much differently in the 

 mare from that of the horse. In the mare it is very short, 

 passing from the neck of the bladder along below the womb and 

 vagina, which is the passage from the outside into the neck of 

 the womb, it opens up into the underside of this passage about 

 four inches in from the outside. This opening is guarded 

 by a small thin valve, and can be felt by passing the 

 finger along the under side of tlie passage v\hich leads into 

 the womb. In the horse this tube is a great deal longer 

 than in the mare, it commences at the bladder, passes 

 along below the rectum or back bowel to just below the anus, her< 



