The Collection of Fishes 433 



a large amount of the fluid. The specimens also require much 

 less attention. An incision should be made in the (right) side 

 of the abdomen to let in the fluid. The specimen can then be 

 placed in formalin. When saturated, in the course, of the day, 

 it can be wrapped in a cloth, packed in an empty petroleum 

 can, and at once shipped. The wide use of petroleum in all 

 parts of the world is a great boon to the naturalist. 



Before preservation, the fishes should be washed, to remove 

 slime and dirt. They should have an incision to let the fluid 

 into the body cavity and an injection with a syringe is a useful 

 help to saturation, especially with large fishes. Even decay- 

 ing fishes can be saved with formalin. 



Records of Fishes. The collector should mark localities 

 most carefully with tin tags and note-book records if possible. 

 He should, so far as possible, keep records of life colors, and 

 water-color sketches are of great assistance in this matter. In 

 spirits or formalin the life colors soon fade, although the pat- 

 tern of marking is usually preserved or at least indicated. A 

 mixture of formalin and alcohol is favorable to the preserva- 

 tion of markings. 



In the museum all specimens should be removed at once 

 from formalin to alcohol. No substitute for alcohol as a per- 

 manent preservative has been found. The spirits derived 

 from wine, grain, or sugar is much preferable to the poisonous 

 methyl or wood alcohol. 



In placing specimens directly into alcohol, care should be 

 taken not to crowd them too much. The fish yields water 

 which dilutes the spirit. For the same reason, spirits too dilute 

 are ineffective. On the other hand, delicate fishes put into 

 very strong alcohol are likely to shrivel, a condition which may 

 prevent an accurate study of their fins or other structures. It 

 is usually necessary to change a fish from the first alcohol used 

 as a bath into stronger alcohol in the course of a few days, the 

 time depending on the closeness with which fishes are packed. 

 In the tropics, fishes in alcohol often require attention within 

 a few hours. In formalin there is much less difficulty with 

 tropical fishes. 



Fishes intended for skeletons should never be placed in 

 formalin. A softening of the bones which prevents future 



