C H APTE R V I. 
THE URINARY SYSTEM. 
This consists of — 
Kidneys. Bladder. 
Ureters. Urethra. 
Kidneys. — These are situated one on each side of the spine 
beneath the lumbar vertebrae. In structure they resemble the 
kidneys of the ox, in that they are lobulated ; the lobes are distinct, 
and vary in number from 5 to 6. The weight is from 6 to 8 lbs. 
Gilchrist gives it as 16 lbs. Their function is to withdraw from 
the blood passing through them certain poisonous products which 
have been elaborated in the system. 
These poisons pass in a state of solution called urine from the 
kidneys through two ducts called the ureters to the bladder, where, 
after a certain quantity has collected, the animal voids it through the 
urethra or passage through the penis. 
The ureters are two tubes which convey the urine from each 
kidney to the bladder. The orifices of the ureters on the inside of 
the bladder are in adults from two to three inches apart. 
The bladder presents no remarkable features ; it serves as a 
reservoir for the urine, and thus prevents the extreme inconvenience 
that would result from having to discharge the urine as fast as it 
is secreted. On the accumulation of a certain quantity, which 
amount varies in different individuals, a very uneasy feeling due to 
nervous influence is experienced, which induces the animal to 
discharge it. The neck of the bladder is supplied with a large 
amount of circular muscular fibres, their office being to keep the 
orifice of the bladder closed. 
The urine is discharged from the body by means of the urethra, 
a membranous canal extending, in the male, from the neck of the 
bladder to the extremity of the penis. In the female it is very short 
and opens into the uro-genital canal. 
The elephant passes water from about 10 to 14 times during 
the 24 hours. This fluid in health has the following characters- — 
specific gravity, 1,004; colour, watery or faint amber, and towards 
the close of the act may be a little turbid ; it is clear and has a 
peculiar characteristic smell, not disagreeable. Any deviation from 
