Cincinnati Society of Natural History. 



drop off, revealing the inside swarming full of mites, and a 

 constant stream of the pests crawling down the pins and 

 spreading to other specimens. My entire collection was 

 threatened. I found heat, sufficient to completely destroy the 

 pest, ruined the specimen. If they were saturated with a 

 solution of corrosive sublimate and alcohol they were safe. 

 But at last I tried the fumes of bi-sulphide of carbon. Pasting 

 up the boxes tight, I made a hole in the side and injected 

 this pungent liquid, closing up the hole tightly afterward, and 

 in this way I succeeded in killing every thing. Dr. Hagen 

 wrote me of this insect : " The most dangerous pest I know ; 

 we once had it in the museum (Cambridge), and though 

 everything was tried, I was unable to get rid of it, until I 

 burned up many boxes of valuable insects." This mite is a 

 very light colored, plump and shining creature, with an un- 

 equaled ability for devouring and reproduction. Fortunately, 

 but fe'w of the American entomologists seem to have had it in 

 their collections. They cost me much time and trouble in the 

 two years I battled with them. As a repellent material to 

 keep pests out, benzine and ether are too volatile ; napthaline 

 is much better. I use the soft flaky scales, and put a pinch 

 in the corners of the boxes. The cones, which are molded 

 011 pins, are good, and can be pinned in the corner of the 

 boxes, but care must be taken that they do not partly evap- 

 orate and fall from the pin, tumble about in the box and break 

 the specimens. When new material is received, it should 

 either be quarantined, or closely watched for some time, to 

 see that it is not infected with eggs which are liable to hatch 

 at any time, and do mischief before being discovered. 



Mr. Ulke, of Washington, washes all coleopterous insects 

 with ether before introducing them into his boxes. Butterflies 

 and moths that are suspected had better be subjected to the 

 fumes of bi-sulphide of carbon, which will destroy any pests 

 that may be about them. I think this will also destroy the 

 eggs of pests, which napthaline will not do. I have been con- 

 vinced that while napthaline fumes will retard the hatching 

 of the eggs, it will not kill them, and as soon as the naptha- 

 line is removed, they are liable to hatch. It is not desirable 

 to attempt to poison all the specimens in a collection to pre- 

 vent them from being eaten, for obvious reasons. It is much 



