18 



INTRODUCTION 



with passe-partout picture binding, to be had at any book- 

 store or photographic supply house. If one such cabinet 

 is prepared each year, a valuable natural history collection 

 will soon result. The centipeds and spiders may be 

 mounted in the same manner as insects, but other animals 

 are better preserved in alcohol or formalin. 



A very neat method of mounting small insects is that 

 of gluing the specimens to a piece of glass and placing 



over them a watch crys- 

 tal held in place by a 

 few drops of glue. 



Pure formalin or for- 

 maldehyde may be pur- 

 chased at the drug store 

 for about fifty cents per 

 pint bottle. One part 

 of this mixed with 

 twenty parts of water 

 makes a solution that 

 will preserve any plant 

 or animal. In case the 

 animal is large, such as 

 a snake or rat, one or 

 two long slits should be 

 made in the abdominal 

 wall so that the fluid 

 may reach the internal organs. Wide-mouthed bottles 

 and fruit jars or small stone jars are the best receptacles for 

 these specimens. 



Painless death may be effected in a half hour by placing 

 any animal in a tight jar or box with a bunch of cotton or 



FIG. 4. Watch-crystal mount. 



