326 DISSECTION OF THE EABBIT. 



brought into very close relation, so that diffusion can readily 

 take place from one to the other. 



In the following account the several systems are described 

 one by one, in order that each may be studied in its entirety 

 as far as practicable, and the mutual relations of its several 

 parts demonstrated. This method is the best, and should be 

 followed whenever possible. If, however, it is intended to 

 perform the whole dissection on a single rabbit, it wUl be 

 found advisable to somewhat modify the order of proceeding. 



For dissection, rabbits should be taken that are not less 

 than six months old, or the reproductive organs will not be 

 fully developed. They may be killed by poiiring a few drops 

 of solution of cyanide of potassium into the ntputh, or else by 

 chloroform, or by drowning or by coal gas in a lethal chamber. 

 If cyanide is used the mouth must be well quashed after death. 



The brain should be removed at once and put into strong 

 spirit. {See p. 378.) 



T. EXTERNAL CHABACTEKS. 



The whole body is covered with hairs variously coloured ; 

 and is obviously divided into- head, neck, trunk, a short tail, 

 and two pairs of limbs. 



A. The Head. 



Note the general form of the head. Determine the position 

 of the mandible, the zygomatic arches, the supra-orbital pro- 

 cesses of the frontals, and other parts of the skull, by feeling 

 through the skin. 



1. The mouth is a small transverse aperture on the under 



surface of the front of the head, bounded by the soft 

 hairy lips. The upper lip is divided by a median 

 cleft, which connects the mouth with the nostrils, 

 and leaves the upper incisors exposed. 



2. The nostrils are a pair of oblique slits at the end of the. 



hairy snout. 



