7« 
THE VETTERINARY SCIENCE 
they pass through a slit or small opening at the back part of 
the muscles of the belly, where they are attached to the under 
part of the hip bone. These slits or openings are known as 
the inguinal rings. They can be felt in the horse by pressing 
the fingers well up into the groins. The descent of the 
testicle is an important point to be remembered. If the 
testicle does not descend into the scrotum the horse is 
known as a rig or ridgeling horse. In this case the testicle is 
not found in the scrotum. At the front part of the testicle 
there is a small ridge called the globus major, and at the 
back of it is another small ridge called the globus minor. 
Passing between these two ridges is another well marked 
ridge called the epididymis. These can be easily seen by 
examining the testicle after the animal is altered or castrated. 
The substance of the testicle is made up of small glands and 
fine tubes. These tubes, as they pass towards the back of 
the testicle, form into larger tubes and finally unite to form 
one called the vas deferens. 
3. Spermatic Cords. — Spermatic cords, or the cords of the 
testicles, are attached above to the inguinal rings or openings 
mentioned before. They are about five or six inches long and 
have the testicles attached to them below. In each cord is found 
a small muscle which goes by the name of the spermatic muscle, 
the rest of the cord being made up of the spermatic artery, veins 
and nerves. Running up at the back of these cords is found 
a tube called the vas deferens. Around the spermatic cords 
and testicles is a serous membrane, one layer being attached 
to the testicle and cord, while the other is closely attached 
around the inside of the scrotum or bag. In this membrane 
are small glands which secrete an oily fluid to lubricate the 
parts, preventing friction when they are jolted about in the 
scrotum. This fluid flies out as soon as the scrotum is cut. 
This is important, because sometimes from a slight injury 
the glands will secrete a large amount of this fluid, thus 
causing the scrotum to look large and swollen. This disease 
is known as hydrocele or water in scrotum or bag. 
4. Vas Deferens. — These tubes are two in number and 
arc situated just behind the spermatic cords. They are about the 
size of a straw and quite hard. They carry the semen up the 
back part of the spermatic cord through the inguinal rings before 
mentioned. They then pass backward and upward, one on 
cack side, to the upper part of the bladder, where they empty 
