Practical Course. « 107 
Examine a specimen, noticing that the whole body is covered with 
hair (as opposed to the feathers of the bird and the scales of the reptiles), 
In the head make out the mouth, nostrils,eyes and ears. Notice that 
the body consists of an interior portion, or thorax, protected by ribs and 
a posterior portion, or abdomen, which is not so protected. 
In the fore-limb make out—(1) the basal joint (arm), which is sup- 
ported by the humerus bone ; (2) the second joint (forearm), which is 
supported by the radius and ulna bones; (8) the wrist, supported by a 
number of small bones (carpals); and (4) the hand, which consists of 
four digits, each terminating in a claw, the thumb being rudimentary. 
In the hind limb make out—(1) the basal joint (thigh), supported 
by the femur, which is articulated to the pelvic girdle of bones that can 
be felt through the skin in the lower portion of the back; (2) the 
second joint (crus), supported by the tibia and fibula bones ; (3) the foot, 
which comprises a basal portion supported by a number of tarsal bones 
followed by five digits, each armed with a claw. 
Feel the skull and vertebral column (back-bone) through the skin, 
noticing how the latter is produced into the tail. In the female notice 
the teats, which communicate with the mammary glands. In the male 
notice the large scrotal pouch, which in the breeding season contains the 
testes, which are of large size. In the case of both males and females 
notice that the anal and urogenital openings are quite distinct from 
each other. 
Pin the animal on its back to the weighted bark, the pins being in- 
serted into the bases of the legs. Immerse it in water, Slit open the 
skin down the entire ventral surface in the middle line. Dissect away 
and pin back the flap of skin on either side. In the female notice the 
extensive mammary glands which lie immediately beneath the skin on 
the ventral surface of the abdomen. 
In connection with the neck, the large jugular vein, which will be 
found on either side, usually gorged with blood, should be made out 
(it conveys blood to the anterior vena cava, which will be noticed in con- 
nection with the heart) ; also three pairs of pale-pink salivary glands. 
These salivary glands are— 
(1) The parotid gland, which is situated on the side of the head 
below the ear ; it pours its secretion into the mouth by a 
duct which opens in the cheek of the upper jaw. 
(2) The sub-maxillary gland, situated in the neck near the middle 
line, at the posterior angle of the mandible. It pours its 
secretion into the mouth by a duct which opens below the 
tongue. 
(3) The sublingual gland, which is much smaller and lies just 
above the sub-maxillary gland, its secretion being poured 
into the mouth by a duct which opens below the tongue. 
