IlEPTILES, BATJRACHlAKS, AND PISHES. 48 



keep fishes, batrachians, and reptiles separate, at least during the 

 preliminary stages of conservation. It must always be remembered 

 that fishes contain much more water than reptiles, and consequently 

 the spirit employed becomes diluted much more rapidly and requires 

 to be changed more frequently. In the case of coniparatively large 

 (2 feet long) and very fleshy fishes, the spirit penetrates very slowly 

 into the interior ; and although the specimens may appear to be 

 in the best condition externally, the inner layers of muscle above 

 and around the vertebal column may be decomposing. It is there- 

 fore necessary to make several deep incisions in the muscular part 

 of the back and tail in addition to those made along the abdomen. 

 Eishes which are loaded with fat, either in the muscles or liver 

 or abdominial cavity, should be placed by themselves in very strong 

 spirit until the greater portion of fat is extracted ; to accelerate this 

 process, the liver should be deeply incised and the masses of fat in 

 the abdominal cavity removed. Before being placed in spirit, the 

 fish should be washed in watei- to lemove as much as possible of the 

 slime with which it is usually coatel. 



Fishes which have lost their scales should not be kept ; such as 

 lose them easily, like the Clupeidw-, should be wrapped in a piece of 

 paper or linen before they are put in spirit. 



It occasionally happens in hot climates that, from some cause, the 

 collector cannot succeed in preserving his specimens from decomposi- 

 tion even with the strongest spirit. In such cases it is advisable to 

 add some arsenic or corrosive sublimate to the spirit ; but the traveller 

 should inform his correspondents that he has adopted this mode of 

 preserving. 



If the colour of the flesh is remarkable, the traveller is recom- 

 mended to take a coloured sketch before skinning it. It is generally 

 important that coloured drawings made from life should accompany 

 a collection ; drawings the originals of which have not been preserved 

 at the time have only a subordinate value. 



Dried skins of fish admit only of a superficial anel incomplete 

 examination, and are easily damaged. This mode of preservation, 

 therefore, should only be adopted when it is impossible to obtain a 

 sufficient supply of spirit and cases, or when there are no facilities 

 for transporting heavy boxes. 



