Zoology.-] NATURAL HISTORY OF VICTORIA. [Fishes. 



Plate 144. 



ECHINORHINUS SPINOSUS (Lin. sp.). 

 The Spinous Shark. 



fGenus ECHINORHINUS (Blainville). (Sub-kingdom Vertebrata. Class Pisces. 

 Order Plagiostomata. Section Selachoidei. Family Spinacidse.) 



Gen. Char. — Dorsal fins two, small, nearly equal, without anterior spine, the anterior edge 

 of anterior dorsal slightly behind the anterior margin of ventrals. No anal fin. Skin with 

 radiated, bony tubercles with conical spine in the middle, very irregular in size and disposition. 

 Mouth crescentic, with a strong fold of skin round the angle. Teeth approximately equal in 

 both jaws, having nearly horizontal cutting edges, from the principal cusp being directed 

 backwards and very little upwards, with large denticles on the anterior and posterior bases of 

 all except the one or two posterior teeth. Nostrils reniform, nearly half-way between eye and 

 tip of snout. Spiracles very small, behind the eye and behind the vertical of the corner of the 

 mouth. No nictitating membrane. Gill openings of moderate size.] 



Description. — Body thick, fusiform. Head flattened above, semi-elliptically 

 rounded in front, the width at posterior edge of orbits about one-fourth greater 

 than the length of the snout to the line connecting them. Nostrils reniform, with 

 long, slender median lobe extending backwards from anterior margin ; the anterior 

 edge a little nearer to tip of snout than to posterior edge of orbit. Dorsal fins 

 higher than long, oblong, rounded, subtruncate at upper posterior edge; first dorsal 

 commencing a little behind vertical of anterior edge of ventrals; second dorsal 

 rather less than the length of the base of the first dorsal behind it. Tail strong, 

 short, raised; caudal fin broad, with a slightly concave posterior edge, and a nearly 

 rectangular, posterior, lower, rounded angle. Ventrals rhombic. Pectorals oblong. 

 Gill openings moderately large, about half of the posterior one above and half below 

 the anterior edge of pectoral ; the anterior one with three-fourths of its length above 

 same level. Lateral line at end of tail running into the caudal fin to the edge, 

 coinciding with junction of upper lobe and fin for a short distance, and thence 

 extending forwards in a nearly straight line a little above one-fourth of the depth 

 from mid-line of back as far as the vertical of the anterior edge of the third gill 

 opening. In all this length it is roughened with rows of minute, slender, hooked 

 spines ; beyond this the line extends forward and a little upwards as two rows on 

 each side of smooth mucous pores, having a transverse similar band connecting 

 them a little behind the vertical of the hind angle of the mouth, the rows of pores 

 extending thence with irregular flexures, widening and converging near tip of snout, 

 but separated in front by a narrow space. Teeth: Ten above and ten below on each 

 side; no tooth in the centre above; one small conical one with a small cusp on each 

 side of base in centre below. Skin: Very thin, with minute, close granules and 

 numerous, radiated bony spines, varying from 1 inch to ^ inch in diameter of base, 

 very irregular in size, shape and distribution, over the whole body and fins, except 

 anterior portion of snout; radiating ridges of spines branching-, and with shorter 

 simple ones between as they diverge ; central spine sharp, smooth, vertical, or with 

 a slight downward or backward curve. Colour : Purplish-brown, paler below ; back 

 and sides with numerous, rounded, darker spots ; whitish under chin and edge of lip ; 

 edges of pectoral, ventral and caudal fins darker brown ; tubercles white. Iris 

 greenish-black, with silvery and bronze-green and blue radiating lines from edge of 

 pupil. 



Vol. II.— Decade XV.-2&. [ 165 \ 



