iti'jj.] 19 



carefully remove the dirt from the surface with a brush. Mould, if 

 not caked by previous attempts at cleaning, peels off readily. 



After the potash is removed by the thorough washin;:;, take the 

 insect out of water and clean it further with the brush, using a mag- 

 nifier if necessary. The legs and antennae should be brushed from 

 base to apex, and can be thus entirely freed from dirt. If due care 

 is used, particularly in cleaning the tarsi, there is little risk of their 

 being broken, as they will be relaxed to some degree by the action of 

 the potash ; indeed, many beetles, as Geodephaga, which are not parti- 

 cularly rigid, can have their limbs brushed out and set off-hand. It is 

 a good plan to pass the pin through a piece of blotting paper on which 

 the limbs can be brushed. Some dirty specimens, particularly those 

 covered with old waxy grease, will require at least a second immersion 

 in potash for some half minute. The grease turns white and opaque, 

 and at the end of that time is usually suiEciently saponified to allow of 

 its removal with the brush. A few^ extremely filthy examples will 

 require from five to fifteen minutes' immersion in potash, and unless 

 very delicate will not be hurt by it. 



The specimen when clean may be allowed to dry, and the labels 

 returned to the pin. If it is pubescent, it may be dipped into alcohol 

 for a few seconds to replace the water ; the alcohol should be removed 

 as far as possible with blotting paper and the specimen quickly dried, 

 preferably by heat. With some beetles it is almost impossible to 

 prevent the hairs matting, but this will occur with any method of 

 cleaning employed. It might answer to immerse them in ether instead 

 of alcohol, and to dry them by any of the methods familiar to those 

 who clean Lepidoptera ; but ether is difiicult to keep and dangerously 

 inflammable, and therefore best let alone. 



The only dirt I have found to defy this method is the sandy 

 substance ingrained in the elytra of such insects as Pimelia. On it 

 the potash is necessarily inert. 



It may be thought that so drastic a cleaning would injure at least 

 the colour or clothing of the specimens. I have not found this to be 

 the case. In all examples I have tried the pubescence has remained 

 quite intact, and in this means of cleaning less violent brushing is re- 

 quired than in any other. I have not experimented on any AVeevils of 

 which the scales are readily detachable, but see no reason why they 

 should suffer more than if washed with soap and water and alcohol. 

 Of course, if soft-bodied beetles arc left unduly long in a solution 

 which will destroy them in time, and thereby come to pieces, the fault 

 is in the judgment of the experimenter and not in the method. It is 



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