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into a variety of ornamental articles. These resemble teeth 

 in their structm-e, and in point of fact are teeth in all but 

 their fmiction. The slaill of the Elasmobranchs is gristly or 

 cartilaginous, and when jaws are represented they consist of the 

 same substance. The Sharks are well supplied with sharp teeth, 

 however. In this division we get fins which represent parts 

 of the fore and hind limbs of the higher animals, in the 

 the pectoral and ventral fins. There is something noticeable 

 about the caudal fin or tail. The spinal column turns rather 

 upwards at the end, and that part of the tail-fin attached 

 above it is smaller than that part below, giving the fin an 

 unequal appeanmce. This is seen in our small English 

 Shark — the Dog-fish. In some of the Eays there is a 

 poisonous spine attached to the tail. The Elasmobranch- 

 gills consist of flattened sacs or pouches in the side of the 

 neck, through which the water flows, which is taken in at the 

 mouth, and, passing on its way the blood-vessels which line 

 the Avails of these pouches, goes out by a row of slits. The 

 eggs of this division are interesting. They are very large, 

 unlike those of our common edible fishes, and contain the 

 young fish enclosed in his leathery or rather parchment-like 

 case. The popular names given to fishes of this group show 

 great variety, for among them we get Devil-fish, an immense 

 Ray; Angel-fish. The Torpedo, too, a term which has grown 

 so familiar to us in connection with another object as to make 

 us almost forget that it originally belonged to an electric fish. 

 The Ganoid division is so named from the peculiarity of 

 their scales, which consist of bone covered with enamel. In 

 some of these the scales overlapped one another like tiles on 

 a roof, but in others they were large, bony plates fitted edge 

 to edge, or arranged at intervals on the skin. We have but 

 few of these Ganoids now living, and these are almost all 

 found in rivers and fresh-water lakes. The Sturgeon is a 

 good example, found in the rivers of Eussia, where it is 

 one of the scavengers of the waters, moving along the 

 bottom, and devouring any decaying substances it may 

 meet with. One species of Sturgeon is sometimes taken in 

 the sea oflf the English coast. By far the most numerous 



