Carolina Madtom 
73 
OCTOBER 
N= 20 
O' 
10 - 
juI 
SEPTEMBER 
N = 92 
JUNE 
N= 18 
l_Lk 
10 
MAY 
N = 92 
STANDARD LENGTH (mm) 
Fig. 5. Length-frequency distribution of Noturus furiosus in spring, summer, 
and fall seasons. At least four age classes are represented. 
milligrams (T) on adjusted body weight in grams (W) was T = -0.001 + 
0.004W (r = 0.52; N = 17). 
In 11 mature males collected from May to July, the GSI ranged 
from 0.001 to 0.007 (x = 0.003). The largest relative testes weight 
(equaling 0.7% adjusted body weight) was that of an 82-mm specimen 
collected 8 June. The GSI of immature males was usually less than 
0 . 002 . 
As in other species of the genus, there was no marked sexual 
dimorphism outside the breeding season. Reproductively mature males 
of N. furiosus had enlarged cephalic epaxial muscles, swollen lips, and 
swollen genital papillae (Fig. 6). The male papilla was much like that 
described for other species of Noturus in the subgenus Rabida (see Burr 
and Mayden 1982a). The swollen heads of males are presumed to 
function in nest guarding and perhaps in nest preparation. 
Reproductive Condition in Females. Throughout the summer there 
was little change in GSI for immature females (range = 0.001 to 0.008; x 
= 0.005; N = 11). Lack of adequate numbers of specimens from the 
remainder of the year prevented a comparison of GSI throughout fall, 
winter, and spring. Ovarian growth in immature N. furiosus is 
