FISHES OF SACRAMENTO-SAN JOAQUIN BASIN. nle75i | 
Three specimens from Rush Creek, a small tributary of Ash Creek, near Aden, Modoc County, 
Cal., collected by Rutter and Chamberlain, September 1, 1898. Type no. 58496, U. S. National 
Museum. Their measurements, in hundredths of the body length, are given in the following table: 
eo] = — Oe ————————— —— —— = —! me — — ———<—<— — —— — 
| 
Length of body. 2 aime A Insertion anal . 0.79| 0.78 0.79 
Length head 7a ; | : Length dorsal. a dl Soilid| 15 
Weyl ies ee asec epee ten oe Heighiidorsal 22255 3 Sas ee St 16 -16 | - 165 
WINMALSL OLD bas eeee cess eee e esas DOVSRILEYS:. acleetoeccae oeMenessae 11 10 } 11 
fnterorbital space... 3222. = oss ene 3 Oi GAmalrave epee coe wees %i | 7 7 
Penprmianonts se cosa set ceees - 105 -10 -10 | Scales in lateral line ............... 82 | 81 81 
Depth caudal peduncle............. -085 | 09 -09 | Scales above lateral line -....-..... 15 | 16 | 16 
Length caudal peduncle.........-.. Sil -16 -16 | Scales below lateral line ........... 11 11 11 
MTISOIHION COXSAL Se = mene =~ ees -49 ~51 -51 | Scales before dorsal ...... 2 eee cee ee) 40 41 
Insertion ventral-......-...-.------ . 56 57 58 | 
Fig. 1.—Catostomus microps, new species. Type. 
5. Catostomus tahoensis Gill & Jordan. Tahoe Sucker. 
Catostomus tahoensis Gill & Jordan, Bul. U.S. Nat. Mus., xu, p. 173, 1878. Jordan and Evermann, Fishes of North and 
Mid. Amer., pt. 1, p. 177, 1896. 
Head 4.4 in length; depth 4.7; eye 5.5 in head, 2.4 in snout, 2.5 in interorbital space, and 1.6 in 
distance between eye and upper end of gill opening. Interorbital 2.4 in top of head; width of isth- 
mus 4.8 in head, 1.5 in distance between eye and gill opening, 1.6 in width of operculum, and equal 
to distance between corners of mouth. (Measurements made on a specimen 6.5 inches long.) Dorsal 
10 or 11, scales 16-90-14. 
Body heavy, profile gradually arched from snout to dorsal; mouth rather small, lips rather large, 
but somewhat variable in size, covered with coarse tubercles; upper lip with two rows of tubercles 
and a few scattered ones representing a third outer row; lower lip with one row across symphysis (3 in 
one specimen with extra large lips), 3 or 4 rounded tubercles and 3 or 4 others coalesced into a contin- 
uous ridge in a longitudinal row through lobes; lower lip deeply incised, the margin of lobes hardly 
reaching vertical through edge of anterior nostril. Orbital rim well developed, leaving a slight groove 
between it and the middle ridge of interorbital, but the thick skin preventing the groove from show- 
ing, the interorbital space being evenly rounded. Origin of dorsal in middle of body, its length about 
1.2 in its height. Insertion of ventrals under fourth or fifth ray of dorsal, their length less than height 
of dorsal. Caudal 1.2 in head, not deeply forked, the middle rays 1.3 in longest. Anal high, reaching 
well upon caudal, height equal to length of caudal; pectoral a little shorter than caudal. Caudal 
peduncle compressed, its thickness above end of anal 0.7 its least depth, which is 2.6 in head. 
Lateral line straight, complete. Peritoneum silvery, thickly dusted with black. Sides often reddish. 
