2oobgj/.-\ NATURAL HISTORY OF VICTORIA. IFishes. 



Plate 75. 



ACANTHIAS VULGARIS (Linn. sp.). 

 The Picked Dog-Fish. 



[Genus ACANTHIAS (Muller and Henle). (Sub-kingd. Vertebrata. Class Pisces. 

 Order Plagiostomata. Sub-order Selachoidea. Family Spinacidae.) 



Gen. Char. — Elongate, slender. Two dorsal fiius, each with a smooth, bony spine on front 

 edge ; pectorals moderate ; ventral fins a little in front of posterior dorsal ; no anal fin ; caudal 

 fin with a very wide, unnotched upper lobe, divided near the middle by the straight end of the 

 body, which is not turned up ; lower lobe small, pointed ; mouth moderately arched, a long, 

 straight, oblique groove on each side of mouth, but no labial fold ; teeth rather small, alike in 

 both jaws, points so much bent backwards that the anterior side forms a straight, horizontal, 

 upper and lower cutting edge ; no nictitating membrane ; spiracles very large, a little behind 

 the eye ; gill-openmgs small, in front of base of pectoral ; a distinct keel on each side of tail. 

 Cosmopolitan.] 



Description. — Slender, tapering*; snout moderately tapering-, narrow, rounded 

 in front ; mouth small, moderately arched, width three-fourths of the distance from 

 tip of snout to its middle; nostrils nearer to tip of snout than to mouth; eye larg-e ; 

 antero-posterior diameter about half the distance from the anterior edge to tip of 

 snout; spiracles very larg-e. Gill-opening's small, the last one over the anterior edg-e 

 of the base of the pectoral. Pectoral fin short, broad ; anterior edge of first dorsal 

 distinctly behind the vertical of the inner posterior angle of pectoral; posterior angle 

 acutely pointed; second dorsal smaller, with posterior angle acutely prolonged. 

 Spines of the two dorsals smooth, moderately arched, sharp at apex, moderately 

 compressed, posterior one longer than the anterior, obtuse in front, hollowed behind, 

 with two sharp, cutting, posterior lateral edges ; ventrals covering the vent, termi- 

 nating a little in advance of the antei-ior edge of second dorsal ; caudal broad, upper 

 lobe ovate, without notch, lower lobe short, pointed. Colour: Above ash-grey, with 

 a few irregular white spots, most distinct in the young ; below white ; fins with a 

 slight brownish tinge, and the dorsals and caudal with an indistinct blackish hue 

 near tip ; eye pale-green. Teeth about 4 in six lines near middle of jaw, about 1 line 

 high, each with a tri-lobed base, and the conical sharp-pointed apex directed so 

 completely backwards that the anterior edge forms a nearly horizontal, slightly 

 convex, sharp, cutting edge. 



Measurements. Male. Female. 



Total length to end of upper lobe of caudal ... 

 Length from snout to origin of 1st dorsal 



„ of base of 1st dorsal... 

 Height of 1st dorsal 

 Length from snout to anterior base of 2nd dorsal 



„ of base of 2ud dorsal 

 Height of anterior part of 2nd dorsal... 

 Length of posterior lobe of 2nd dorsal 



„ from anterior origin of base of caudal fin 

 to tip of upper lobe 

 Depth of lower lobe of caudal 



[23] 



