THE CAT 209 



urogenital organs, together with the anus and the urogenital 

 openings, the former of which is dorsal to the latter. It contains 

 also the pelvic girdle, by means of which the skeleton of the 

 hind limbs is joined with the trunk. The forward motion of the 

 animal is accomplished largely by means of the hind limbs, 

 the front limbs being of use principally in supporting the anterior 

 end of the body and in changing the direction of movement. The 

 connection of the pelvic girdle with the trunk is consequently 

 much firmer than that of the pectoral girdle. The pelvic girdle 

 forms a complete arch, the bones of which are immovably joined 

 with one another and also with the spinal column by sutures. 



The Tail. The caudal region is the most flexible of all. It is 

 also of the least apparent importance to the animal, and varies 

 much in size in different cats. In Manx cats it may be entirely 

 absent ; in Angora cats it is very long and bushy. In water verte- 

 brates the tail is a very important part of the body, since it is 

 the principal organ of locomotion. Land vertebrates have in- 

 herited it from their aquatic ancestors; and as it is no longer 

 needed for locomotion, it is put to a variety of other uses, or may 

 even be absent altogether. 



The Appendages. Two pairs of appendages are present, the 

 fore and hind limbs. Each is made up of three divisions, a prox- 

 imal, a middle, and a distal division. In the fore limb these are 

 the upper arm, the forearm, and the wrist and hand respectively. 

 The hand has five digits, provided with retractile claws. The 

 first digit, or thumb, is above the others and is more or less 

 rudimentary. Note the walking-pads on the sole of the foot ; on 

 the side opposite to the thumb is a small pad which is over the 

 pisiform bone of the wrist. Identify the three divisions of the leg ; 

 also the shoulder joint and the elbow. 



In the hind limb the proximal division is the thigh, the middle 

 division is the shank, and the distal division is the ankle and 

 foot, the latter having four digits, which are provided with re- 

 tractile claws. Note the walking-pads on the foot; also the 

 heel, which projects back from the upper end of the ankle. 

 Identify the three divisions of the leg; also the hip joint and 

 the knee, 



