APPENDIX. 



4G7 



their proper relative positions. The comparison of bones 

 with the descriptions in his practical text-book will be an 

 excellent training in biological observation, free from the 

 unpleasantness that accompanies the first unskilled dissec- 

 tion of a fresh rabbit. But he must see that every point 

 described is clearly verified on the specimen ; the habit of 

 shirking difficulties is easy to acquire and difficult to get rid 

 of. Drawings should be made -of the bones, if only for 

 practice. 



If a dog's head can be got (preferably that of a young 

 animal) it can be treated in the same way, the brain being 

 cleaned out by alternately wriggling a bent wire through 

 it and washing out the debris by a strong stream from a 

 tap. Failing a dog's, a cat's skull will do very well. The 

 rabbit's has a very narrow palate as its chief peculiarity : 

 it should be kept for guidance in dissecting the head. 



All bones should be thoroughly dried after being cleaned. 

 If they smell unpleasantly, soaking them in water to which 

 a little chloride of lime has been added will cure this, but 

 too strong a solution will rot the bones. The best pre- 

 ventative of smell is thorough cleaning. Soap and a nail- 

 brush are very useful in the final stages. 



Having mastered the skeleton, the student will be in a 

 better position to carry on ordinary dissection. If, however, 

 he finds this very unpleasant to him, our advice would be 

 to leave the rabbit, and start on the frog, returning to the 

 rabbit when he has gained experience in dissection on the 

 smaller animal. 



A good deal of bleeding is sure to occur in the earlier 

 dissections of frog and rabbit by a beginner. The application 

 of ferric chloride solution to the cut vessel will make the 

 blood clot rapidly and stop further bleeding. 



For detailed instructions in dissection we must again 

 refer to the books already recommended. For the study of 

 the rabbit's brain, which is especially difficult, we offer the 

 following suggestions : Take & fresh rabbit (cut off its head 

 if you like), and skin the dorsal side of head and neck ; 

 remove also the muscles running from the occipital region 

 to the neck as far as you can. During the rest of the 

 operation keep a dried rabbit's skull by you for comparison 



