262 



Acipenseridce. 



a. Swimming-bladder, dried. (Siberian Purse Isinglass.) 

 Note. This specimen is labelled as above, but does not occur in Dr. 

 Pereira's catalogue, and the name is put among the doubtful species in 

 Giinther, Cat. Fishes in Brit. Mus. 



812. A. GULDENSTADTII, Brandt 8f Ratzeburg. (Osseter.) 



* a. Swimming-bladder inflated and dried, from the 



Wolga. 



6. Ditto, cat open and dried. (Astrachan Leaf Isinglass.) 

 Note. This species has 29-32 lateral shields, which are coarsely radi- 

 ated, and a short obtuse snout about one-third of the length of the head. 



813. A. Huso, L. (Great Sturgeon, Beluga, or Bielaga.) 



* a. Swimming-bladder inflated, from the Wolga. 



t 6. Ditto cut open, bleached and dried. (Beluga Leaf Isin- 

 glass.) *I 



Note. This species has 40-45 lateral shields, and the snout is without 

 osseous scutes above. Beluga leaf consists of the bladder cut open ; the 

 pieces are 12 or 14 inches in diameter. 



814. A. STELLATUS, Pallas. (Sewruga.) 



* a. Swimming-bladder, inflated and dried, from the Wolga. 

 6. Ditto, cut open and dried. (Astrachan Leaf Isinglass.) 



Note. Isinglass is also yielded by A. ruthenus, L. (Sterlet.) See Per. 

 Mat. Med., vol. ii., pt. ii., p. 770. A. stellatus has 30-35 lateral shields, 

 and the snout is very long and narrow, forming nearly two-thirds of the 

 head. Astrachan leaf isinglass occurs in pieces 9-12 inches long, and 

 from 2-4 inches broad in the upper part, tapering to about 1 inch at the 

 lower end. The three specimens marked with an asterisk are those men- 

 tioned by Pereira as being presented to him by Professor Ludewig of St. 

 Petersburg, Oct. 22, 1847. See Per. Mat. Med., vol. ii., pt. ii., pp. 770, 771. 



815. A. STURIO, L. (Common Sturgeon.) 



a. Small Thames sturgeon, stuffed. 



Note. This specimen is not quite 4 feet long. The common sturgeon 

 is distinguished from the other species by having 26-31 lateral shields, 

 and 11-13 dorsal shields, and by the pointed snout occupying about 

 half the length of the head. See Redwood, Supplement, p. 151 ; Moquin- 

 Tandon, Med. Zool., p. 182 ; and Giinther, Cat. Fishes in Brit. Mus., vol. 

 viii., p. 334, for distinctive characters of the various species. 



816. ACIPENSER SPECIES. 



a. Astrachan long-staple isinglass. Two specimens. 



b. Patriarch, or finest short-staple isinglass. 



* c. Astrachan cake isinglass. (LepeschJci.) 

 d. Astrachan fragments. (Kroschki.) 



Note. Specimen d is a dirty inferior isinglass, in irregular lozenge- 

 shaped pieces about 1 inch in diameter, and a quarter of an inch in thick- 

 ness. 



* e. Siberian lump isinglass, from the Baikal. 



Note. This specimen consists of small cakes about 2 inches long and 

 I inch thick. 



