A METHOD OF KEEPING ALCOHOLIC SPECIMENS. 



By F. C. BisHOPP, 

 Bureau of Entomology, U. S. Department of Agriculture. 



The following method of preserving alcohoHc specimens has 

 been used at the Dallas laboratory for the Bureau of Ento- 

 mology for a number of years. It has been found to be more 

 satisfactory than any other system tried. 



The specimens to be preserved are placed in the smallest 

 size shell vials, which will contain the specimens, and a brief, 

 finely printed label. For minute specimens, such as mites, 

 mallophaga, etc., shell vials 25 mm. in length by 8 mm. in 

 diameter are used. In fact, this size vial is employed for all 

 specimens which can be placed in them without crushing. 

 About three other sizes of shell vials are employed for the larger 

 material. For short, thick specimens short vials of large 

 diameter are used. The shell vials containing the specimens 

 and labels are stopped with a small compact wad of absorbent 

 cotton and the vials are then inverted and placed in a larger 

 container. The container employed by us is a shell vial, 

 100 mm. long, by 28 mm. in diameter. A small layer of 

 absorbent cotton is placed in the bottom of the container 

 before the vials are inserted. This prevents danger of cracking 

 the bottom when the small vials are dropped in. Each con- 

 tainer is limited to one species, or if very little material of a 

 certain kind is to be collected one of the large vials may contain 

 a genus or even larger groups. 



Ordinarily, however, each container is limited to a species, 

 and a label bearing the name of the species is placed on the out- 

 side of the container, as is also the container number. Containers 

 of the above diameter will hold conveniently seven or eight of 

 the smallest size vials in one layer, and two layers may be placed 

 in each. The container is then filled with alcohol in order to 

 cover the vials and a good quality of cork used to close it. In 

 the Dallas collection the material is then filed systematically 

 by orders and alphabetically by genus and species under these. 

 The containers are kept in wooden racks sufficiently wide to 

 hold two of the bottles with a partition between and twelve 

 inches long. A label is placed on the end of the rack to show 

 the material it contains, and cardboard riders are set on the 



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