20 



be examined only by great labor and serious injury to the 

 skin. The skins themselves were often left flat, or rolled 

 up, or greatly over-stuffed, or otherwise distorted, with the 

 ears crumpled, the toes and feet bent at all angles, and the 

 tail shrunken or broken, so that through the faults of care- 

 less taxidermy accurate measurements were almost impos- 

 sible, and even approximate ones were difficult to obtain. 

 Well-prepared and carefully labeled specimens were the 

 exception. Large numbers of the smaller mammals, it is 

 true, were preserved in alcohol, and were thus available for 

 measurement and for anatomical examination, but such 

 material is almost useless for the study of color characters, 

 and very inconvenient for comparative study in respect to 

 specific and subspecific differences. Specimens of mammals 

 preserved in spirits or other solutions are also in this re- 

 spect very untrustworthy, from the fact that the coloration 

 of the pelage is so liable to undergo great change, espec- 

 ially if wood alcohol or alum solutions happen to be the 

 preservative employed. 



Very different indeed from all this is the present method 

 of forming collections of the smaller mammals. Now series 

 of specimens of the same species, from the same locality, 

 numbering from ten to fifty or more, are almost the rule ; 

 and it is considered essential, wherever possible, to have 

 the series duplicated at different seasons of the year, in 

 order to show the seasonal variation. Of course this has 

 not yet been done for all species, but it is the aim to collect 

 as far as possible on this plan. The skull is removed from 

 the skin, carefully cleaned and preserved separately, and 

 cross-reference numbers refer to both skin and skull, so 

 that they may be studied together. Several measurements 

 of the animal are taken by the collector, who has special 

 instructions in this regard, before skinning, and recorded on 

 the label ; the skin is then carefully filled to the natural 

 size as indicated by the measurements, the tail vertebrae 

 being replaced by a wire; then, in pinning the specimen out 

 to dry, the tail and the feet are carefully extended in straight 



