1. ACIPKNSEU. ;i33 



1. A.CIPENSER*. 

 Acipenser, Artedi. 



Hufio, Sturio, Sterleta et Ilelops, Brandt ^ llatzehury, ii. pp. 3, 340. 

 Lionisciis, Acipenser, Ilelops, Autaceus, Slurio et Huso, Fitziiujcr (^'• 

 Ileckcl, Aiui.Jricn. Mita. i. p. 200. 



The rowvS of osseous sc-utes not confluciit on the tail. Spiracles 

 present. Ciiudal rays surrounding the extremitj' of the tail. 



Inhabitants of the temperate and arctic i-egions of the northern 

 hemisphere, ])criodically entering rivers. Some species entirely 

 confined to fresh water. 



The geographical distribution of the Sturgeons is nearly identical 

 with that of Sahno. 



Si/nopsis of the )S2)ecies. 



The number of species has been so multiplied, and they have been 

 founded on such trivial characters, that the critical study of the 

 literature is a very diificult task. To select and understand such 

 characters as may be used for specific distinction, ichthyologists 

 ought to choose a species of which the greatest number of examples 

 of all ages is available. Thus, for instance, on taking the common 

 European Sturgeon, it will be found that the relative breadth of the 

 snout, the form and number of the irregular scutes on the head, the 

 rudimentary ossifications of the skin, are subject to great variations, 

 individual and dependent on age. On the otlier hand, the number 

 of lateral shields, considered by some naturalists (who have compiled 

 their descriptions from the accounts given bv different authors) to 

 be variable, proves to be very constant, young immature examples 

 having generally a few less, the hindmost on the tail not being de- 

 veloi)cd. 



Professor Golowatschof, who appears to have had very good oppor- 

 tunities of examining great numbers of Sturgeons in Southern llussia, 

 points out some of the variable characters used for distinguishing 



* !.< Acipenser Irevis, Agass. Lake Siqxr. p. 267. — Long description of the 

 head of a Sturgeon from Lake Superior, 4^ feet long. 



2. schvpa (? Glddenst. A'oy. Comni. Petroj). xvi. p. 533), Brandt 



4- Ecdz'cbvrg, ii. p. 20, tab. L fig. 3 (not p. 3.j(), tab. 1 a. fig. 2).— Eiver 

 Irtish'. — Lat. scut. 40-4."), dorsal 14. 



3. dauricus, (rcnrf/i, Bcvierk. licise Runs. Reich, i. p. 3.52; Brandt 



i.y Rat;eb. Medic. Zool. ii. p. 12 ; Acipenser orientalis, I'allas, Zoogr. 

 Ross.-A.f. iii. p. 107. — River Amur. — Lat. shields 38-40, dorsal 14-16. 

 — The account given bv Fitzinger ^ Heckel (A7>7i. Wiev. Mus. i. p. 318) 

 is a compilation of descriptions gi\ en by various authors, in which evi- 

 dently several si)ecies are confounded. These two authors state, for 

 instance, that the number of lateral shields varies between 38 and 65 I 



4. (Antaceus) caryi, DumtrU, hmiv. Arch. Mus. 1867, p. 169, pi. 12. 



fig. 2. — California. 



5. — •- ( — — ) putnami, Dumvril, I.e. p. 178, pi. 13. fig. 1. — California. 

 6. dabryanus, Dinnrrd, Xni/v. Ar^h. Mu.'s. iv. p. 98, pi. 22. fig. 1. — 



Yangtzekiang. 



7. sturioidcs. Malm. Forhandl. Skniid. Ntrf. fti^c mode. Kjobnh. I860, 



p. 618. — RiverGota.— Dorsal plate.s 1 1, lateral 38. — Tliis species is cer- 

 tainly distinct from A. f.ttirio, but has not been properly distinguished 

 from otiier European and American species. See ]>. .'iS','. 



