ACIPENSER HUSO. 129 



Spec. Char. Body dusky blucish above; sides blucisb ; 

 abdomen slightly silvery., wbite ; fins greyish ; cirri 

 short ; skin rather smooth ; lateral tubercles so mew hat 

 obliterated. 



AvT«xaioj : JElian, lib. 14, cap. 23, 26. Atillus; Plin. Hist. Nat. 1. 9, c.15 ; Belon, 

 Aijuat. 102. Atilns Pado ; Rondel, dc Pise, ii p. 173. Huso ; Adrov. de Pise. 

 p. 504. Huso Gornianoruni ; Willughb. Ichthy. p. 243, t. p. 7, f. 1, 2 ; Raii y Syn. 

 p. 113. Acipcnscr tubcrculis carens; Artedi, Syti. p. 92. Acipenser Huso; 

 Syst.Nat. Gmcliri, i. p. 1487 ; BlocJt, Entomol. iv. p. 86, t. 129 ; Shaw, Zool. 

 v. t. 159. 

 Le grand Esturgeon, Fr. ; Adello, It.; Der JIuusen, Gcr. ; Beluga, Russ. 



The Isinglass Sturgeon is one of the largest of the cartilaginous 

 fishes, growing to the length of twenty or twenty-five feet. In its 

 general form it resembles the common Sturgeon, from which it 

 principally differs in colour, and in having the tubercles on the back 

 and sides much less protuberant. It inhabits the Northern, Caspian, 

 and Mediterranean Seas, ascending the larger rivers and lakes, and 

 returning to the sea again in autumn, after having deposited its 

 spawn. It is taken in the greatest abundance in the Wolga and 

 the Danube. 



The body is long, slender, pentagonal, gradually tapering towards 

 the tail, and covered throughout the whole length by five rows of bony 

 tubercles, rounded at the base, radiated, and of a conical form : of 

 these tubercles one row is situated on the back, and two rows on 

 each side. In aged individuals these tubercles along the sides are 

 smaller, and those on the sides sometimes altogether wanting. 

 The head is large and thick, sloping on each side, and covered 

 with bony plates ; the snout is long, obtuse, and furnished be- 

 neath, before the mouth, with four worm-shaped beards or cirri . 

 the mouth is placed beneath the upper part of the head, and con- 

 sists of an oval orifice, as in the common sturgeon, entirely 

 destitute of teeth, but much larger, and furnished with very thick 

 crescent-shaped lips. The gill-cover, on each side is composed of 

 a smooth simple roundish plate. The skin is smooth and viscid. 

 The pectoral fins are oval ; the dorsal fin large, and situated very 



