38 



FISH GALLERY. 



of Portugal and Madeira. Each dorsal fin is provided with a 

 spine, which, however, is sometimes so small as to be hidden below 

 the skin. The mouth is wide ; the lower teeth have the points 

 inclined outward ; the upper teeth are erect and triangular, or 

 narrow and lanceolate, with a single cusp (see jaws 82). In 

 Centrina (83) the trunk is rather elevated, triangular in section, 

 with a thick fold of the skin extending along each side of the 

 ventral surface. Each dorsal fin is provided with a strong spine, 

 which is largely concealed in the substance of the fin. The teeth 

 of the lower jaw are erect, triangular, and finely serrated ; those of 

 the upper jaw are slender and conical, and form a group at the 

 front of the jaw (see jaws 84). 



The Spinous Shark, Echinorhinus spinosus, 86, has a short 

 bulky body and a short tail. The dorsal fins are small and have 

 no spines ; the first dorsal is opposite to the pelvic fins. The 

 teeth are equal in the upper and lower jaws ; they are very oblique, 

 the point being turned outward, and having one, two or three 

 horizontally directed denticulations on each side. Embedded in 

 the skin are scattered, fiat, circular tubercles, each with a small 

 central spine. The nostrils are midway between the mouth and 

 the end of the snout ; the spiracle is small. The Shark lives 

 mostly in deep water ; it occurs in the Mediterranean and the 

 Eastern Atlantic. 



In the Greenland Shark, Lcemargus borealis (sketch 87 and 

 specimen 1138 hanging from the rail in front of Wall-case 4) all 

 the fins are small : the dorsal fins are without spines, and the first 

 is set at a considerable distance in advance of the pelvic fins. The 

 nostrils are near the extremity of the snout; the jaws are feeble; 

 the shagreen is uniform. The upper teeth are small, narrow, and 

 conical ; the lower teeth are numerous, each with the point so 

 much turned aside that the inner margin forms a cutting edge. 

 The Greenland Shark is an inhabitant of the Arctic regions and 

 grows to a length of fifteen feet. Although harmless to man it 

 attacks "Whales and bites pieces out of their sides. 



The Angel-fish or Monk-fish, Rhina squatina, 88, is the sole 

 living species of the family Rhinidae ; the genus is represented 

 in the Lithographic Stone (Upper Jurassic) of Bavaria, where 

 complete skeletons occur. The mouth is anterior and the gill- 

 openings wide and lateral in position. The depression of the body 



