232 ENTOMOLOGY. 



merits, or the common white arsenic of commerce. A pint 

 and a half of alcohol will take about fourteen grains (troy) 

 of arsenic. The living insect, put into this preparation, 

 absorbs about y^Vo °f its own weight. When soaked in 

 this liquor and dried, it will be safe from the ravages of 

 moths, Anthrenus or Dermestes. This liquid will not 

 change the colors of blue, green, or red beetles if dried after 

 soaking from twelve to twenty- four hours. Hemiptera and 

 Orthoptera can be treated in the same way. 



A stay of a month in this arseniated alcohol mineralizes 

 the insect, so that it appears very hard, and, after drying, 

 becomes glazed with a white deposit which can, however, 

 be washed off with alcohol. In this state the speci- 

 mens become too hard for dissection and study, but 

 will do for cabinet specimens designed for permanent 

 exhibition. 



Another preparation recommended by Laboulbene is 

 alcohol containing a variable quantity of corrosive subli- 

 mate, but the latter lias to be weighed, as the alcohol evap- 

 orates easily, the liquor becoming stronger as it gets older. 

 The strongest solution is one part of corrosive sublimate to 

 one hundred of alcohol ; the weakest and best is one-tenth of 

 a part of corrosive sublimate to one hundred parts of alco- 

 hol. Insects need not remain in this solution more than 

 two hours before drying. Both of these preparations are 

 very poisonous and should be handled with care. The last- 

 named solution preserves Speci mens from mould, which will 

 attack pinned insects during damp summers. 



A very strong brine will preserve insects until a better 

 liquor can be procured. Professor A. E. Verrill recom- 

 mends two simple and cheap solutions for preserving, 

 among other specimens, the larvae of insects " with their 

 natural color and form remarkably perfect." The first 

 consists of two and a half pounds of common salt and four 

 ounces of nitre dissolved in a gallon of water and filtered. 

 Specimens should be prepared for permanent preservation 

 in this solution by being previously immersed in a solution 



