240 VERTEBRATES. 



skin. On what parts of the body is the hair longest ? 

 What exposed parts are bare, and why ? Compare the 

 color of upper and lower surfaces. What is the character 

 of the hair on the soles of the feet ? 



Examine the claws. Are they well adapted for weapons 

 of offense ? 



Note the length and position of the tail. Take the fol- 

 lowing measurements : the distance from the tip of the 

 nose to the base of the tail ; the length of the tail ; the 

 height of the ears ; the length of fore and hind legs and 

 of fore and hind feet. 



Note the close approximation of the ears, and the wide 

 space between the eyes. What is the advantage to the 

 rabbit, of this arrangement? 



Why does a rabbit run more easily up hill than down ? 



Note that the upper lip is cleft below the nostrils, ex- 

 posing the front teeth when the lips are retracted. The 

 advantage of this in gnawing is very obvious. 



Structure. Dissect the rabbit on a broad piece of 

 board, into which tacks may be driven. Use an injected 

 specimen. 1 Make a circular cut through the skin, around 

 the base of its neck, and pull the skin forward over its 

 head, wrong side out, carefully dissecting it free from the 

 parts which lie beneath. At the base of the ears note 

 the tubular, basal cartilage supporting each ear, and see 

 also the attached muscles, which change the position of 

 the ears. Cut off the ears : this will expose the external 

 auditory canals. At the eyes, in removing the upper and 

 lower lids with the skin, an imperfect third eyelid (or 

 nictitating membrane) should be left behind. Remove the 

 skin of the head entirely, breaking or cutting its attach- 

 ments at the lips. Note the hairiness of the inside of the 

 cheeks. 



1 For a method of injection see Appendix, p. 286. 



