THE RABBIT {Lepus cuniculus) 



First Day 

 External Features. 



The body is thickly covered with hair. The head is connected with the 

 trunk by a short neck. The tail is very short. Note the following features : — 



(i) The Head. Notice the general form ; the rounded cranial region, the 

 elongated facial region, and the cheeks (zygomatic arches). Note the 

 following parts : — 



(a) The mouth, on the under surface at the front of the head, 

 bounded by the soft upper and lower lips. The upper lip is 

 cleft in the middle. This " hare-lip " cleft connects the 

 mouth with the nostrils. 



{b) The nostrils, two oblique slits at the end of the snout. 



(c) The eyes, at the sides of the head, are protected by an upper and 

 a lower eyelid, and by a nictitating membrane or third eyelid. 



{d) The vibrissas, long stout tactile hairs on the sides of the snout 

 and about the eyes. 



(e) The large external ears or pinnse. 



Open the lips and note the diastema, a gap between the 

 front incisors and the back teeth on each side. The hairy 

 lip extends over the gap into the mouth cavity. 



(ii) The Trunk. It consists of two portions, the anterior part or thorax, 

 and the posterior part or abdomen. Note the following : — 



(a) The anus, under the tail. 



(6) The openings of the perineal glands, bare patches at the sides of 

 the anus. The characteristic smell of the rabbit is due to the 

 secretion of these glands. 



(c) The urino-genital opening, in front of the anus. In the male 

 it is small and is situated at the end of the penis, which is 

 retractile within a loose sheath of skin (the prepuce). In 

 the female it is a large and slit-like vulva. 



{d) The scrotal sacs of the adult male, two pouches situated one on 

 either side of the penis and containing the testes. 



{e) The teats of the female, four or five pairs along the ventral 

 surface of the abdomen and thorax. The ducts of the mam- 

 mary or milk glands open through the teats, 

 (iii) The Limbs. 



{a) The fore-limbs are short. Each limb is composed of an upper- 

 arm, a fore-arm, and a manus or hand. The manus has 

 five clawed digits, the innermost of which, the poUex, does not 

 reach the ground. 



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