200 U.S. NATIONAL MUSEUM BULLETIN 2 82 



A^. miurus has crossed from the Mississippi Valley into the Pearl 

 River system of Mississippi and Louisiana, and has been recorded 

 from the Tangipahoa River, an apparent error for the Natalbany 

 River, Louisiana. 



Many literature records of miurus cannot be assigned to any 

 species with assurance; they are listed without comment in the 

 synonymy of miurus. 



Remarks. — There has long been doubt concerning the identity of 

 the specimens that formed the basis of the name Notorus miurus 

 Jordan. Most members of the subgenus Rabida have at one time or 

 another been identified as miurus by Jordan and others, and the types 

 have not been seen or studied by recent workers. Some confusion has 

 arisen because two other species of the subgenus Rabida also occur in 

 Indiana near the type-locality. Both of them, Noturus eleutherus and 

 Noturus stigmosus, could easily have been included in the type-material. 



Diagnostic characters from Jordan's (1877b, pp. 370-377) original 

 description that point to the correctness of the lectotype selection 

 are: pectoral spines strongly serrated, extremely strong and curved, 

 the upper jaw longest, the "adipose fin continuous . . . interrupted 

 by a notch which does not quite break its continuity . . . much 

 mottled blackish and yellowish; margins of dorsal, anal and caudal 

 fins, and a broad patch in the middle of the adipose fin, definitely 

 black." These characters taken in combination with the locality 

 (White River, Indiana) indicate the species herein called Noturus 

 miurus and eliminate others. The figures of the types given by Jordan 

 (1877d, pi. 39) have little value; that in Jordan and Evermann 

 (1900, pi. 29, fig. 68) illustrates, instead, a specimen of Noturus 

 juriosus; the figure of Schilbeodes miurus in Forbes and Richardson 

 (1909) is the first to represent adequately the species recently generally 

 identified as miurus and which as concluded here must bear that name. 



Etymology. — The name miurus (Greek) is defined as meaning 

 curtailed, and presumably refers to the general shortened appearance 

 of some specimens. 



Relationship. — The strong resemblance of this species to flavater 

 &nd Jlavipinnis and their structural similarities are sufiicient to justify 

 their association as the miurus species group. 



Ecological considerations. — The geographic distribution of 

 miurus is a clue to its requirements. It seems to avoid clear, cold, fast 

 waters; at least it is not present in the cool upper waters of the White 

 River in Missouri and Arkansas in association with. Jlavater, and it has 

 not penetrated into the colder upper Great Lakes. It lives in lowland 

 or base-level streams which have some current, in many streams 

 (chiefly pools below riffles) with moderate current, and in lakes. It 

 mostly avoids rock and gravel riffles, especiaUy those with fast water; 



