PISCES. 71 



Order V. Sturiones {Ghondrostei Muell.). 



Skeleton cartilaginous. Lower jaw attached to the cranium by 

 means of a suspensory formed of three parts. Rays of branchioste- 

 gous membrane none. Tail asymmetrical, with fin adhering be- 

 neath the spine of back. 



Family VII. Sturiones. (Characters of the order those also of 

 the single family.) 



Acijjenser L. Body with an armour of osseous scutes, disposed 

 in fi^^e longitudinal rows. Head produced beyond the mouth into 

 a triangular apex, flat below. Cirri in front of the moutli inferior 

 and edentulous. 



Scapliirhynchus Heckel. Temporal foramina none. Body behind 

 the pectoral fins covered everywhere with large scales, depressed. 

 Sp. Scaphlrhynclms Rafincsquii Heckel, Annalen des Wiener Mitseums l, 

 Wien, 1836, pp. 76 — 78, Tab. viii ; North America, in the Ohio and Mis- 

 sissipi ; attains a lengtli oi. 2'- — 3'. 



Acijyenser L. Temporal foramina. Rows of scutes extending as 

 far as tail, skin naked in the interstices, I'ough with small dispersed 

 squamules. 



Sp. Acipenser sturio L., Block, Tab. 88, Brandt u. Ratzeb. Mediz. Zool. 

 II. Tab. 3, fig. I, the sturgeon ; attains a length of 6 — 10 feet ; the dorsal 

 scutes are highest in the middle ; the filaments beneath the head are with- 

 out appendages and terminate in a point. In other species they are flat 

 like a band {Acipenser husoli., Block Ichth. Tab. 129, Brandt u. Ratzeb. 

 1. 1. Tab. I a, Supjil. fig. i), or with small appendages like fringes. 



The sturgeons live in the seas of the northern hemisphere, and from 

 thence ascend different rivers. They attain a remarkable size (Acipenser 

 huso, ex. gr. 25 feet). Most of the species belong to Eastern Europe and 

 Western Asia (Black Sea, Caspian Sea). From the roe caviar is prepared, 

 from the swimming-bladder isinglass. To prejjare the last (Hausenblase 

 trom Hansen, the German name of Huso), of which the best kind comes from 

 Astracan, the swimming-bladder is laid in warm water, cut open, washed 

 and exposed to the air, so that the internal silvery membrane lies upper- 

 most ; this having been removed by rubbing, the external membrane is 

 dried. 



Compare on this genus Brandt u. Ratzeburg Mediz. Zool. 11. s. i — 30, 

 s. 349 — 355, and Fitzinger u. Heckel Annalen des Wiener Museioms, i. 

 s. 261 — 326, Tab. 25 — 30. In some species there are two rows of ven- 

 tral scutes, little developed, or in old individuals they are very flat (Acip. 

 ruthenus L.), on which are founded the statements of some writers that 

 there are sturgeons with only three rows of scutes. 



