COLLECTING FISHES. 77 



tion. The ventral fins must also be cut loose from the pubic 

 bones at the point where they are articulated. Now take the 

 cut edge of the fish skin between the left thumb and forefinger, 

 and with the cartilage-knife carefully cut the skin free from the 

 flesh. Be careful not to disturb the white layer of color pig- 

 ment which is spread like a silver lining of feeble tin-foil over 

 the inside of the skin. This is what gives the fish its silvery 

 color, and if skinned off or scraped away the skin will look like 

 colorless parchment. Whatever you do, do not disturb that color 

 lininy. Proceed with the skinning until the skin has been de- 

 tached from the entire upper side of the fish. This brings you 

 to where the dorsal and caudal fins are inserted.* 



Now turn the fish over, and proceed as before, as far as you 

 can go. You presently reach the caudal fin, which must be cut 

 loose from the end of the vertebral column as far back in the 

 skin as possible. When this has been done, the skin and the 

 fleshy body still hang together by the attachment of the rays 

 of the dorsal fin to the interhaemal spines. Cut these apart 

 with the scissors, from back to front, close up to the skin, which 

 brings you to where the vertebral column joins the skull. You 

 will make very short work of that, which frees the fleshy body 

 from the skull. Now scrape away the surplus flesh from the 

 inside of the skin, wash it thoroughly, remove the gills (if they 

 are not to be studied), and lay the skin flat upon its side in your 

 tank of alcohol. 



By thus preserving the skins of fishes, instead of whole speci- 

 mens, a great number of really large specimens can be pre- 

 served in a small quantity of alcohol, for at the last they can be 

 packed together, heads and tails, precisely like sardines. 



SKINNING CARTILAGINOUS FISHES. Sharks, Rays, etc. The skin- 

 ning of a shark or saw-fish calls for no special instructions in 

 addition to the foregoing, except that the long, narrow, pointed 

 tail requires to be slit open along the right side of its upper 

 lobe for a considerable distance. Remember the principle that 

 wherever there is flesh, a way must be made so that it can be 

 removed, or at least reached from the inside by the preserva- 

 tive. Of the skull, nothing is to be left attached to the skin 



*Some operators open a fish in a straight line along the middle of one side, but 1 have 

 never beeu able to see any reason for this preference. 



