314 INSECT LIFE. 



Clips for Slides. — The glass slides upon which microscopic 

 objects are mounted are fastened to blocl<s by means of clips which 

 are made from wire (Figs. 280 and 281). 



Destruction of Museum Pests. — Even when specimens 

 are kept in tight cases, it often happens that the museum pest finds 

 its way into a case and attacks the specimens. The presence of 

 this tormentor is indicated by a fine dust that falls to the bottom 

 of the case from the infested specimen. All of the cases in a col- 

 lection should be searched once a month for this indication of the 

 presence of pests. If a case is found to be infested, the pests can 

 be destroyed by pouring a tablespoonful of carbon bisulphide in one 

 corner of the case and tightly closing the case. This substance 

 evaporates rapidly and will destroy the pests without injuring the 

 specimens. It can be obtained of any druggist. 



If it is necessary to store away a collection for more than one 

 month, a naphtha cone should be put in each case and strips of 

 paper pasted over the crack between the top and bottom. Naphtha 

 cones can be obtained of dealers in entomological supplies. 



Mold. — In certain regions where the climate is moist speci- 

 mens are very liable to become covered with mold. The best 

 method of preventing this is to keep a small quantity of carbolic 

 acid in the cases. 



