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It is found that, by mounting the majority of the Sauria and 

 Batrachia on plaster tablets, in the jars of alcohol, their value 

 for purposes of exhibition is greatly enhanced. This takes 

 considerable labor ; but, once mounted, they will need no further 

 attention for a long period. Many specimens have been sent to 

 correspondents of the Museum. Every request for duplicates 

 has been complied with. Yet the bulk of what has gone out 

 has been much exceeded by that of the arrivals. 



The space allotted to Reptiles and Batrachia in the System- 

 atic Exhibition Room, as well as that in the North American 

 representation, has been occupied. 



The upright storage cases which have been erected for the 

 alcoholic collections have prevented the sudden changes of 

 temperature, and the frequent breakages done to them. 



The checks upon evaporation introduced by the use of these 

 cases, of copper cans, and of a preparation of wax for the 

 stoppers of the jars, have so cut it down that its amount is very 

 small indeed compared with what it was formerly. 



The instances in which the cans suffer by corrosion are few, 

 and the expense on this account will prove a mere trifle in 

 comparison with the amount saved in the prevention of evapo- 

 ration, and of breakage in glassware, by their use. This applies 

 as well to the alcoholic material in other departments. Alcohol, 

 which has been reduced by the addition of water to 75 per 

 cent or lower, requires changing so much sooner than if left full 

 strength that it is in reality more expensive. There is also in 

 its use an increased danger of decay in the specimens, while cans 

 containing specimens perfectly preserved in strong alcohol are 

 the least likely to be corroded. 



The incidental correspondence — requests for information, 

 identifications, &c. — is increasing. A careful attention to all 

 questions has resulted in increasing the interest and activity of 

 our correspondents, from which the Museum of course receives 

 direct benefit. 



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