GILBERT: FISHES OF THE SUBGENUS LUXILUS


 A comparison of N. albeolus and N. cornutus is presented in tables
3, 6, 7, and 9 through 15, and in figures 15C through 15F.
 DESCRIPTION. Fin ray and scale row counts and proportional
measurements are listed in tables 6 through 15. Characters men-
tioned in the diagnosis are not repeated in the following paragraph:
 Mid-dorsal stripe grayish-black, slightly more than half as wide as
eye, and extending around base of dorsal fin; a light streak about the
same width as dorsal streak extending along body on either side of
dorsal streak (this character not nearly so clearcut and distinct as in
N. cornutus); below each of these light streaks is another dark streak
of the same width and slightly lighter color than the dorsal streak
(this and the preceding character evident only in breeding males);
pigment on chin and anterior part of gular region either present or
absent; pinks and reds usually absent on body, rarely present on snout
of breeding males; pink or red coloration usually absent from all fins
at all ages, occasionally present on dorsal, caudal, anal, and pelvic
fins of breeding males; dorsal fin slightly dusky, but never greatly
darkened in breeding males; other fins plain; nuptial tubercles present
over head, the tips pointing straight upward, possibly not as well
developed as in N, cornutus and N. chrysocephalus (relatively few
tuberculate specimens of albeolus have been examined).
 VARIATION. Notropis albeolus exhibits the most interesting mor-
phological variation found in any form of Luxilus. Differences in
body proportions in particular contribute to a rather perplexing prob-
lem involving its correct taxonomic status. In general specimens from
the New and Roanoke drainages seem similar in appearance, as do
those from the Neuse, Tar, and Cape Fear systems. This similarity
is particularly noticeable in body shape; specimens from the New
and Roanoke tend to be more slender and terete, those from the
other drainages are usually deeper and more compressed. Propor-
tional measurements for individuals from the New and Roanoke aver-




 e.




 Figure 11. Adult Notropis albeolus, USNM 101339, 76.5 mm SL, from Waqua
 Creek at highway 140, Brunswick County, Virginia.


1964