THE CAT 207 



Observe the color of the animal and note if the color patches 

 are bilaterally symmetrical. The domestic cat is probably de- 

 scended from the Egyptian wildcat, Felis maniculata, the color 

 of which is mottled gray, very much like that which is so common 

 among domestic cats ; domestication, however, has resulted in a 

 wide range of variation in color, from pure white to pure black. 

 Observe the difference in color and also in the length and texture 

 of the hair between different regions of the animal's body: the 

 back and the belly, the head and the trunk, the inner and outer 

 sides of the leg, etc. 



Observe the general form and shape of the body. The trunk 

 is a laterally compressed, cylindrical structure ; the head is large 

 and compact, the neck short, and the tail long. The rather short 

 legs with their sharp retractile claws, the lithe, muscular body, 

 and the strong jaws and large teeth fit the animal for a predacious 

 life in the woods and fields. 



The body may be divided into four regions: the head, neck, 

 trunk, and tail. The trunk may be further divided into the 

 thoracic, lumbar, and sacral subregions. 



The Head. This body region articulates with the vertebral 

 column by two occipital condyles. It is very solid and compact, 

 all the bones being closely knit together and the upper jaw being 

 firmly joined with the cranium. This feature is correlated with 

 the structure of the teeth. Instead of these being all alike in 

 form, as is the case among most of the lower vertebrates, and 

 being of use principally in seizing the food, they are specialized 

 to perform a variety of functions, the front teeth to seize the food 

 and the back teeth to chew it. 



The mouth is large and is guarded by upper and lower lips. 

 The nostrils are a pair of large openings at the end of the project- 

 ing nose. The eyes are large, and each is protected by three eye- 

 lids : the upper lid, the lower lid, and the nictitating membrane, 

 or third eyelid. This third lid is an opaque membrane at the inner 

 corner of the eye, which moves across it. Take hold of it with 

 forceps and pull it across the eye. There are no eyelashes, the 

 whole surface of the lids being covered with hair. A pair of large 

 external ears is present. 



