210 U.S. NATIONAL MUSEUM BULLETIN 282 



a species to find a mate of its own kind in the breeding season. This 

 is suggested by the observation that, with the exception of the Indiana 

 specimen, the hybrid Noturus are from near the edge of the range of 

 one of the parents, where its distribution interfingers into that of 

 the other species. For example, one of the parent species of the Okla- 

 homa hybrid is rare at the hybrid locality, as determined from exten- 

 sive collections made at the locality. 



The following is a summary of hybrids in the family Ictaluridae: 

 O'Donnell (1935, p. 483) and Thompson (1935, p. 492) recorded 

 three or four specimens from the Rock River, at Rockford and Sterling, 

 Illinois, "which appear to be hybrids" between Ictalurus punctatus 

 (Rafinesque) and Opladelus [Pylodidis] olivaris (Rafinesque). These 

 fish were not described or illustrated, notes concerning them were 

 not made, and the specimens can no longer be found. Although both 

 species are known to occur together, because of the apparent distant 

 relationship of Ictalurus and Pylodidis the identification of these 

 individuals as hybrids is subject to considerable doubt. 



Six specimens have been recognized as hybrids between species of 

 Noturus. The most noticeable characteristics of these hybrids are 

 the abnormal pectoral spine and peculiar coloration. Two other speci- 

 mens of uncertain identity that may be hybrids are discussed under 

 Noturus gyrinus. 



Noturus gyrinus (Mitchill) X Noturus miurus Jordan 



Plates 3 (fig. 12), 21 (fig. 2) 



Schilbeodes nocturnus (Jordan and Gilbert) [misidentifications]. — Osburn, Wick- 

 liff, and Trautman, 1930, pp. 170, 174 (near mouth of Portage R., Ottawa 

 Co., Ohio; one specimen). — Hubbs and Lagler, 1939, p. 26 (Great Lakes 

 basin); 1941, pp. 63-64; and Gerking, 1945, pp. 74-75 (L. Erie basin). — 

 Hubbs and Lagler, 1947 [and 1949], pp. 71, 73 (possibly the L. Erie basin 

 record is a hybrid).— Trautman, 1959, pp. 31, 43, 442. 



Rabida nociurna (Jordan and Gilbert) [misidentification]. — Driver, 1942, p. 254 

 (Great Lakes basin). 



Schilbeodes miurus (Jordan) X Schilbeodes mollis (Hermann). — Trautman, 1948, 

 pp. 166-173, pi. 1, figs. 2, 5, 8 (description and comparisons; S. shore of L. 

 Erie, 2 mi. E. of Port Clinton, Ohio). — Slastenenko, 1960, p. 74 (compiled). 



Material studied 



UNITED STATES: Indiana: USNM 199583 (1 specimen), Laughery Cr. 

 [near mouth], near Aurora, August 13, 1957; collected with 4 A'^. miurus and 31 

 A^ gyrinus. Michigan: UMMZ 157214 (1 specimen), Huron R., N. of Milford, 

 sec. 13, T. 2 N., R. 7 E., Oakland Co., May 23, 1949. UMMZ 167302 (1 specimen), 

 Huron R., just below Kent Lake Dam, sec. 1, T. 1 N., R. 6 E., Livingston Co., 

 June 8, 1954, reportedly collected with both parent species. New York: CU 42514 

 (1 specimen), dredged channel just below lake road, Cayuga Lake, Seneca Co., 

 July 24, 1960. 



