186 BULLETIN OF THE BUREAU OF FISHERIES. 
Head conical, its depth at occiput about 1.6 in its length; mouth oblique, jaws even, or lower 
included. Top of premaxillary on level with lower edge of pupil; shortest distance across preorbital 
about .8 of eye. Tip of lower jaw rounded, not truncated or trenchant as in symmetricus. ,Caudal 
peduncle deep and compressed, but little tapering, its depth equal to snout and eye in larger specimens. 
Teeth 5-4, sometimes 44. 
Description based on specimens 55 to 158 mm. long from South Fork Pitt River. 
The following table indicates the variation in scale and ray counts and number of teeth: 
Specimens having— 
Dorsal Anal 
rays— . rays— 
| 
| - — —— = 
9. | 10.] 7} 8.19. 
Locality. Lateral ine— 
| 44.) 45. 
Teeth 5-4. 
. SS. 59. 60. G1. 
_ Teeth 4-4, 
Goose Lake...............- Bee Mie 
South Fork Pitt River 
Pitt River, Canby... 
Ash Creek, Aden... 
Pitt River, Bieber. 
Fall River. ........ 
Paes 
as 
ron! 
Hat Creek, Cassel. . Sal ae & 
Wolf Creek, Greenville. .... Jos-[--- = 
Totals 5 coeeasese se 1/5/12) 9)7¢)9) 12/97 3) 5) 2)2 1)3 30 
The head varies from 0.264 to 0.32, being longest in specimens from Goose Lake, which vary from 
0.29 to 0.82. The average size in other localities is about 0.28. 
The depth varies from 0.254 to 0.31, being least in the specimens from Wolf Creek, a tributary of 
Indian Creek, near Greenville, Plumas County. Goose Lake specimens have the depth slightly greater. 
while the deepest specimens come from South Fork Pitt River. 
The eye and interorbital vary inversely with the size of the fish. The snout varies but little, 
and the depth of the caudal peduncle only from 0.115 to 0.138. The other measurements show consider- 
able variation, but the variations are not characteristic of localities. 
The scales range from 44 to 61, averaging about 49 or 50, being somewhat more numerous in speci- 
mens from Hat Creek. The number of scales above the lateral line is usually 11 or 12, sometimes 13; 
the number below is 6 or 7. 
The dorsal raysare 8, 9, or 10, and the anal 7, 8, or 9, without reference to locality. The teeth are 
usually 54, but occasionally 44. Half of the specimens examined from Hat Creek have the teeth 4-4. 
The greatest variation is in the head. Its shape is even more variable than its length, the South 
Fork Pitt River and Goose Lake specimens exhibiting the two extremes. The former has a short 
triangular head (when viewed from the side), the profile steep, the mouth oblique, but much less so 
than in the Goose Lake specimens, the mandibles not forming a distinct angle with the lower outline, 
and the nape swollen. The Goose Lake specimens have the head long and slender, xppearing quad- 
rangular when viewed from the side, the profile more nearly horizontal, the mouth very oblique, the 
lower jaw forming a distinct angle with the lower outline. and the nape not swollen. All possible 
intergradations are found in other localities, and a full series of intergradations are known from Klamath 
Lake. 
Loca Disrrisution. 
Loeality. Stream or lake. Collector. | Name as reported. | Authority. 
Orepon con nae ee cere tae Goose Lake. ..............: Conese sss sae {ir encase mexorends (Gone 
California. © 5-2 a. s- ocnonc nase eee ee OOS. oe Soe enn aes z 
South Fork Post-office South Fork Pitt River 
Canby-"- te. . a Pitt River = 
Aden... Ash Creek. 
Pittville. Pitt River. 
Dana. - Fall River. 
Gagsel 32 5 Hat Creek- 
Greenville, Indian Valley - Wolf Creek 
