148 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Agosia robusta Rutter, new species. 
Body heavy, highest above insertion of pectorals; the ventral outline curved almost as much 
as the dorsal. Head 3.8 to 4 in body; snout blunt, but little overlapping the premaxillary and 
never extending beyond it; mouth oblique, barbels usually absent, present on 10 to 50 per cent of 
specimens from any one locality. Fins small; D. 8; A. 7; pectoral about equal to head behind nostril, 
variable; caudal moderately forked, middle rays two-thirds length of longest; rudimentary caudal 
rays forming prominent keels along upper and lower edges of tail; margin of anal slightly rounded, 
the anterior rays not all produced, not extending beyond posterior rays when fin is depressed. 
Lateral line nearly always incomplete, but with scattered pores frequently extending to base of 
caudal; scales 56 to 77, varying about 12 in any one locality. Usually two dusky lateral stripes, the 
upper extending from snout to caudal, the lower branching off from the upper behind the head 
and ending along base of anal; cheek abruptly silvery below lateral stripe; tinged with orange 
about lower jaw, upper end of gill-opening, and at base of lower fins. 
Type (No. 50589 U. S. Nat. Mus. ). Collected in Prosser Creek by Rutter and Atkinson. 
Taken in Spring Creek, Willow Creek, Susan River, Little Truckee River, and Prosser Creek. 
Coregonus williamsoni Girard. 
Abundant, in streams tributary to Truckee River. A “native white-fish,” probably this species, 
is reported from Bigler (Tahoe) and Donner lakes in the California Fish Commission Report for 
1883-84. 
Salmo henshawi (Gill & Jordan). Lake Tahoe Trout. 
Occurs in only the Truckee Basin, and taken in Little Truckee River, Sage Hen Creek, and 
Prosser Creek. The black spots of sides much larger and fewer than in Salmo irideus. 
Salmo irideus Gibbons. Rainbow Trout. 
Readily distinguished from the above by the very small and numerous black spots, as well as 
by the absence of the red blotch on inner edge of mandibles. Introduced into Truckee Basin, and 
possibly also into Honey Lake Basin. It was observed in Susan River and Prosser Creek. 
Salvelinus fontinalis (Mitchill). Brook Trout. 
This species has been introduced into Prosser Creek, where specimens were taken. 
Cottus beldingii Eigemnann & Eigenmann. Blob. 
Palatine teeth wanting; no prickles on skin; lateral line broken under posterior rays of dorsal, 
sometimes a few pores on caudal pedunele, usually none. Top of head covered with minute 
pimples. Dorsal spines 6 to 8, dorsal rays 15 to 19, anal rays 11 to 14. 
Found in Susan River, Little Truckee River, Sage Hen Creek, and Prosser Creek. 
