Jordan and Ever maun. — Fis/ies of North America. 105 



opposite the vent. Shields generally opisthocentrous with a strongly 

 hooked spine; the surface very rough. Space between lateral and dorsal 

 rows of shields with about 5 series of stellate plates interspersed with 

 smaller ones; last dorsal shield moderate; more than | the one before 

 it. Snout about as in A. tra'usinoiitnnus, sharp in the young, becoming 

 blunt with age, usually rather shorter than the rest of head. Barbels 

 nearly midway between tip of snout and mouth. Gill rakers scarcely 

 higher than broad, about 17 in nuniber. Upper lobe of tail with some 

 scattered plates. Caudal fulcra not enlarged. Lower lobe of caudal 

 short and blunt, little more than i the length of the upper. Dorsal 

 plates 10 (9 to 11); lateral 26 to 30; ventral 9 (7 to 10). Anal nearly 

 as long as dorsal and mostly behind it. D. 33 to 35; A. 22 to 28. Depth 

 7^ in length ; head 4^. Pacific coast, ascending the rivers from San 

 Francisco northward, reaching a large size ; less abundant than A. irans- 

 montanus, and smaller in size ; not used for food, being reputed poisonous. 

 (medium, moderate; tostrum, snout.) 



Acipenser meiUrosiris, Ayr'ES, Proo. Cal. Ac. Sci., i, 1"), 1854, San Francisco; Gunther, Cat., 



vni, 342, 1870; Jordan & Gilbert, Synopsis, 8G, 1883. 

 Acipeitser agaaxizii, alexandri, and oUijopellis, Dumeril, Nouv. Arcli. Mus., iii, 181, 183, 184, 1867, 



San Francisco. 

 Aci}jeiiser agassid, GuNTHER, Cat., viii, 344, 1870. 

 Acipenser acnlirostris, Gunther, Cat., viii, 344, 1870. 

 Acipeiixer mediroslris, KiRSCH & Forpice, /. c, 249, 1889. 



147. ACIPENSER STURIO, Linnaus. 



(Common Sturgeon.) 



Shields not strongly striated ; stellate plates small, in about 10 rows, 

 with smaller ones interspersed; last dorsal shield moderate, more than 

 i length of one before it. Snout rather sharp, nearly as long as the 

 rest of the head, becoming comparatively shorter and blunter with age. 

 Barbels nearly midway between mouth and tip of snout, shortish, not 

 reaching the mouth. Gill rakers small, slender, pointed, sparse, not 

 longer than the pupil. Fulcra roughish, not enlarged. Lower lobe of 

 tail rather sharp. Anal more than i dorsal, placed mostly below it. 

 Anterior rays of pectoral thickened. D. 38; A. 27. Dorsal plates 10 to 

 14; lateral 29 (27 to 36); ventral plates 9 (8 to 11). Olive gray, paler 

 below. Atlantic coasts; ascending rivers of northern Europe and the 

 United States. 



The American Sturgeon (var. oxyrhijnchus, Mitchill) has the number 

 of lateral plates generally fewer (27 to 29 instead of 29 to 36, as in Euro- 

 pean examples). The stellate ossifications are also said to be somewhat 

 rougher than in the European form. New England to Carolina; abun- 

 dant, {nturio, sturgeon.) (Eu.) 



Acipenser slurio, LlNNA.us, Syst. Nat.,x, 1758, 237; Gunther, Cat., vin, 342, 1870. 



Acipervfer ojrijrhynchus, MiTCHiLL, Trans. Lit. it Phil. Soc. N. Y., 1, 402, 1814, tin- American 



•form, New York; Jordan & Gilbert, Synopsis, 86, 1883. 

 Slurin viilgariis, IIafinesque, Indicp, 41, 1810, Palermo. 

 Acipetiser liclitciisleiiil, latiroslris, hospitiis, l)intiips,>iii, allilns, anil iinrrrlli of European iiitliors; A. 



viitchiUi, New York; la'ninrrifli, James River; girdi-di, Maryland; tiincinrlihiiis, New York; 



megalaspis. Lake Champlain, iiiilbrrti. New York, hainh, Maryland; xlnrfn, Boston; 



holbrooki, Charleston; and hconlii, New York;PuMt:RiL, Nouv. Aicli. Mus., iii, 18<i7. 



