43° /iPPENDIX. 



Eefore commencing the study, read that portion of the preface 

 which explains the use of iertns 0/ direction (page VII). 



Note that the page on which any figure is found may be deter- 

 mined by consulting the list of figures given in the Table of Contents. 



THE BONES. 



The bones will of course be studied from dried specimens. 

 These may be prepared once for all and kept in the laboratory from 

 year to year. A number of mounted skeletons of the cat should be 

 at hand ; these must be prepared by some one who has skill in such 

 work. 



Preparation of Separate Bones. — For preparing the separate bones 

 the liquid-soap process recommended by Wilder and Gage (" Ana- 

 tomical Technology," p. 107) will be found most convenient. This 

 is as follows: The skin and soft parts are removed as far as possible 

 without injury to the bones. 



Make the following " liquid-soap " mixture: 



Soft water 2000 cc. 



Strong ammonia 150 cc. 



Nitrate of potash (saltpetre) 12 grams. 



Hard soap 75 grams. 



Heat these together till a homogeneous mixture is formed. Now 

 immerse the bone or bones to be cleaned in a licpiid composed of 

 four parts water to one part of the above liquid-soap mixture. Boil 

 forty minutes; pour off the licpiid and renew it. lioil about half an 

 hour longer; then remove soft parts with fingers, scalpel, and brush. 

 The bones may be boiled as much longer in the mixture as is neces- 

 sary to make the soft parts come away easily. If they are boiled too 

 long, however, the epiphyses will separate from the bones. This 

 is especially likely to occur in young skeletons, which must therefore 

 not be boiled so long as the bones of an old cat. 



Skeletons prepared in the following rough way are useful for 

 many purposes. The entire body of the cat, or a single limb, is 

 placed in the liquid-soap mixture (after partial removal of soft parts), 

 and boiled till the muscles may be removed, but the ligaments, 

 holding the bones together, remain. Clean thoroughly without 

 removing the ligaments, and allow to dry. The bones are thus held 

 together in their natural positions. Skeletons so prepared are not 

 elegant, but are frequently useful. 



Disarticulation 0/ Skulls. — The bones of the skull may be sepa- 

 rated as follows: Clean the skull in the liquid-soap mixture, as 

 above described. Then fill the cranial cavity with dry rice, beans, 

 corn, or some other seeds that swell much on imbibition of water. 

 Cork up the foramen magnum, and place the skull for twelve to 

 twenty-four hours in water. The swelling of the grain will partially 



