594 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 117 



tubercles. In the absence of tubercles, as well as in other characters, 

 the subgenus Ulocentra seems most closely related to the Etheostoma 

 {Etheostoma) zonale species group. 



Winn (1958b, p. 172) noted that males of two of the undescribed 

 forms of Ulocentra (from the Barren and Green rivers of Kentucky) 

 were larger than the females, had larger anal, first dorsal, and pelvic 

 fins, and lacked breeding tubercles. These two species usually spawn 

 in a nearly vertical position with the male moimted on the female's 

 back (Winn, 1958a; 1958b, fig. 4). 



Subgenus Allohistium Bailey 



There is only a single species: E. cinereum Storer. The testes and 

 pigmentation of a spring-caught male (CU 37281, Tennessee, Cum- 

 berland R., March 26, 56 mm.) are well developed and breeding 

 tubercles are absent. Males in six collections taken later in the year 

 (ANSP, UMMZ, USNM) have shghtly developed testes and also 

 lack tubercles. 



Subgenus Nothonotus Agassiz 



There are seven described species in this subgenus: acuticeps Bailey, 

 camurum (Cope), jordani Gilbert, maculatum Kirtland, moorei Raney 

 and Suttkus, rufilineatum (Cope), and tipjjecanoe Jordan and Ever- 

 mann. Apparently this subgenus lacks breeding tubercles, although I 

 have not examined adequate breeding material of acuticeps or 

 tippecanoe. 



Bailey (1959) described the sexual dimorphism in color as well 

 marked in Nothonotus. He wrote (p. 3) : "All species are colorful, 

 varying from subdued to gaudy. The breast is blue or green in adult 

 males .... The body is lined with dark in several species ; the soft 

 dorsal, caudal, and anal fins are dark-edged in some, and the fins may 

 be somber or brightly colored with red, orange, or green .... No 

 species has a submarginal red or orange band in this [first dorsal] fin." 

 For E. acuticeps, he reported (p. 8) : "It is probable that no nuptial 

 tubercles are developed since adults taken in June, and nearly ready to 

 spawn, have none." Raney and Suttkus (1964) reported that nuptial 

 tubercles are absent in E. moorei. Raney and Lachner (1939) noted 

 that males of E. maculatum attain a larger size than females. In addi- 

 tion, Winn (1958b, p. 172) reported that males have larger anal, first 

 and second dorsal, pectoral, and pelvic fins than females. He de- 

 scribed the genital papiUa of the breeding female as flattened and 

 flowerlike, and he did not find breeding tubercles on the male. E. 

 maculatum spawns under rocks and the male defends the nest (Raney 

 and Lachner, 1939). E. camurum spawns in gravel around or under 



