4 ELEMENTS OF MAMMALIAN ANATOMY. 



Canis familiaris; the wolf, Cams lupus; the pig, Sus scrofa; 

 the red deer, Cervas elephas; the elephant, Elephas 

 Africamts; the ourang-outang, Simla satyrus; and man, 

 Homo sapiens. 



METHODS OF PRESERVING MATERIAL. 



Alcohol has been widely used as a preservative, but owing 

 to the fact that it is expensive and quickly evaporates from 

 the specimen exposed to the air, thereby rendering the parts 

 dry and brittle, its use has been largely 

 supplanted by formalin. Formalin, CH 2 O, 

 is often sold under the names of formose, 

 formol, formine, formalosa, and formal- 

 dehyd. It can be purchased for about 

 thirty cents a pound. For preserving any 

 animal or plant, the concentrated 40% 



formaldehyd is diluted with water in the 

 FIG. i. SPECIMEN . - r .1 j 



J AR- proportion of ninety-five parts of the lat- 



ter to five parts of the former. It is 

 evident, therefore, that one pound of formaldehyd will make 

 about ten liters of preserving fluid. 



The specimens may be kept a year or two without chang- 

 ing the formalin in ordinary stone jars with covers, but 

 for permanent preservation the glass jar with the ground- 

 glass cover should be used (Fig. i). 



Preparation of Vascular System. To render the vessels 

 plainly visible and distinguish the arteries from the veins, 

 it is advisable to inject the former with a red mass and the 

 latter with a blue mass. These fluid masses should be of 

 such a character as to harden in a short time after injection, 

 so that they will not run out when the vessels are cut during 

 dissection. 



A syringe of hard rubber, having a capacity of about two 



