SHARKS AND RAYS OF BEAUFORT, NORTH CAROLINA. 243 



Formerly large quantities of these skins were used for polishing wood, ivory, etc., for which they 

 arc excellent, owing to their roughness, hardness, and durability; but the great improvements made in 

 preparing emery compositions and sandpapers have resulted in substituting them almost entirely for 

 polishing purposes. However, a small demand yet exists for shark skins for cabinetworkers' use. 



The principal uses made of the skins of sharks and allied fishes at the present time are for covering 

 jewel boxes, desk ornaments, cardcases, sword sheaths, sword grips, and a great variety of small arti- 

 cles for which the tuberculous markings peculiarly adapt them. The demand for these purposes, 

 however, is small and restricted, and each producer has to develop his own market. Comparatively 

 few of these skins are prepared in the United States, and diligent search among the tanneries and leather 

 stores will result in the finding of only a few skins. Many, however, are prepared in France, Turkey, 

 and other countries of southern Europe, and also in China and Japan. 



A Parisian manufacturer has made quite a reputation tanning the skins of a species of Malabar 

 shark into morocco, and establishments in Turkey make green leather from the skin of the angel shark 

 found in the Mediterranean Sea. The skin of the diamond shark obtained in the North Sea, and so 

 called because of the shape of the markings or protuberances, is used to cover the sword grips of German 

 officers, and for this purpose is not surpassed by any material obtainable. Some parts of the skin of 

 certain varieties of sharks when dried and hardened take a polish equal to that of stone and bear a 

 strong resemblance to the fossil coral porites, and are much used in the manufacture of ornaments and 

 jevvelr>-. 



In preparing them for the use of cabinetmakers, shark skins are merely cleaned and not tanned. 

 The hard, dry skins are soaked in lukewarm water for three or four days, shaved on the flesh side to 

 remove siu'plus flesh and muscular tissue, and then dried. The skins of some species of sharks are so 

 hard that they can not be shaved. The appearance of these skins is improved by bleaching, using 

 chloride of lime and sulphuric acid. The durability of some of them is remarkable, outwearing many 

 sheets of sandpaper of equal area. 



In tanning shark skin for leather or ornamental purposes an alum process is generally employed. 

 Each establishment usually has its own particular method, but the general process is much the same, 

 consisting of a preliminary soaking, liming, bating, and fleshing, and then tanning or preserving in an 

 alum compound. The hard skins are first soaked in water four or five days and then in limewater for 

 two to six days, depending on the condition of the texture, temperature of water, etc. The skins are 

 washed free of lime and bated in bran water, then shaved on the flesh side to remove all excess of flesh 

 and the like. The alum solution in which they are immersed is composed of a pound of alum and one- 

 fifth pound of salt to a gallon of water. The skins remain in the solution two or three days, with occa- 

 sional stirring. On removal they are dried and are then ready for manufacturing. 



Class CHONDROPTERYGIA. The sharklike fishes. 

 Subclass PLAGIOSTOMIA. The sharks, skates, and rays. 



KEY TO THE ORDERS AND FAMILIES OP PLAGIOSTOMIA REPRESENTED IN THE BEAUFORT, N. C, REGION. 



I. Antacea: Body subfusiform ; pectorals not attached to the head; gill openings lateral. 

 a. Body subcylindrical. 



b. Anal fin present; two spineless dorsals. 

 c. Nictitating membrane absent; spiracles present. 



d. First dorsal fin inserted more or less in advance of ventrals. 



e. Caudal fin not lunate; upper lobe two or more times length of lower, with a notch below 

 toward tip; sides of caudal peduncle not keeled. 

 /. Last gill slit entirely in front of pectoral fin; teeth long, subulate, with a slender cusp on 



each side Carchariidae. 



jff. Last gill slit above pectoral base; teeth triangular, compressed; caudal longer than 



body Vulpeculidae. 



ee. Caudal fin lunate; caudal peduncle with a keel on each side; last gill opening entirely 



in front of the pectoral Isiuidse. 



dd. First dorsal fin over or behind the ventrals; last gill slit above base of pectoral. 



