THE NARWHAL. 



147 



of the tail is from fifteen to twenty inches. There is no 

 dorsal fin, but a sharp ridge runs down the centre of 

 the back, the edge of which is generally found to be 

 rough, and worn, as if by rubbing against the ice. At 

 an early age the narwhal is blackish gray on the back, 

 with numei*ous darker spots and markings running into 

 each other, forming a general dusky black surface. The 

 sides are almost white, with dusky and more open 

 markings; the under surface is white. In adult speci- 

 mens the ground-colour of the back is yellowish-white, 

 with markings varying from dark gray to dusky black, 

 and of a roundish or oval figure, with interspaces of white 

 or yellowish-white between them. The skin resembles 

 that of the common Greenland whale {Balcena mysti- 

 cetus), but is thinner. (Fig. 96.) The female narwhal 

 produces a single young one at a birth, which she 

 nourishes with milk for several months. 



The Narwhal. 



To the rapidity, the great powers, and the ferocity of 

 the narwhal when attacked, many writers have borne 

 testimony. Its form is admirably adapted for cleaving 

 the waters, and we can well believe that the shock of its 

 weapon, driven full tilt against an enemy, must produce 

 a terrible effect. The ribs of the stoutest boat would 



