L388 BULLETIN OF THE BUREAU OF FISHERIES. 
The following table indicates the variation in scale and ray counts, giving the number of specimens 
in which the various counts were made: 
Number of specimens having— 
- Dorsal | Anal 
Locality. Scales— rays— | rays— 
az. | 48. | 49. | 50. | 51. | 52. | 53. | 54. | 55.| 56.| 8. | 9. | 10. 
San Joaquin River, Pollasky...-.....------------------ Baa ell ee 
Kings River, Centerville.........-.--------- 2 
Kaweah River, St. John Channel.........-.-- 
Tule River, Porterville ss. a. 8 eee a enn 
Chouchilla River near Raymond... 
Merced River, Livingstone..--- 
Merced River, Benton Mill.-_--. 
Stanislaus River, Parrot Ferry 
North Fork Merced River 
Mariposa Creek....-- 
North Fork Consumn a Boal Bose B 
North  RorkiPittonlvens oe ee ee ene eee 
Mobales tate eee eee eee ee eee s}10|12/17| 7|13| 6| 9 13) 2)slay aw 
Rew 
ois! 
Br pode 
Nom DON 
The insertion of the dorsal varies from 0.57 to 0.61 of the body length from the tip of the snout. 
The dorsal rays are 10 or 9, one specimen from Mariposa Creek having but 8. Anal8or9. Usually 
nearly all specimens from one locality have the same number. In these numbers the last double ray 
is counted as two when both divisions are divided. 
The caudal peduncle is characteristically slender in symmetricus. Typically its depth is 0.09 or 
0.10, which is the size in specimens from San Joaquin at Pollasky, Kings River, and St. John or Kaweah 
River. It is 0.10 in specimens from Thomas Creek, Stanislaus River, and Merced River at Livingston 
and Benton Mill; 0.10 or 0.11 from Battle Creek, North Fork Merced, Mariposa Creek, Chouchilla and 
Tule River; and 0.11 or 0.12 from North Fork Consumne River and North Fork Pitt River. 
The size of the caudal fin varies much. Usually it is about one-third as long as the body, but in 
specimens from Mariposa Creek, North Fork Merced River, North Fork Consumne River, and North 
Fork Pitt River it is only one-fourth as long as the body. From other localities all possible intergrada- 
tions may be obtained. Those specimens with the longest fin have it the most deeply forked. 
The variations noted fall into three groups, though hardly of such a nature as to permit of even 
subspecific distinction. 
First is the Mariposa form, which differs from the Pollasky or typical form in having a smaller head, 
smaller eye, smaller fins, especially the caudal, one ray fewer in dorsal and anal. deeper caudal peduncle, 
and greater variation in the number of scales, 48 to 56. Specimens from North Fork Merced River at 
Bower Cave are very similar, but have a slightly larger eye, and the head is of typical size. The speci- 
mens of the 2 localities have independently developed similar variations, as there is no direct connection 
between the two streams. Mariposa Creek isa mere brook, emptying into the dry bed of Mariposa River. 
Its water reaches the San Joaquin River only after heavy winter rains. Mariposa Creek is south of 
Merced River, so that it and North Fork Merced do not even drain opposite slopes of the same water- 
shed. There is a fall in the latter stream below Bower Cave, which prevents the ascent of fishes from 
the main river, Rutilus and Salmo being the only fishes in the North Fork above the fall. 
The second variation is the Pleasant Valley form. So far as measurements go this form runs close to 
the Mariposa form, but its general appearance is quite different. The head is slender, not conical, the 
depth at occiput less than in any other form, the snout very blunt. These characters show in a less 
degree in specimens from Tule River and Battle Creek. The caudal peduncle is deep, the caudal fin 
intermediate in size between that of Mariposa and Pollasky forms. The horny sheath is well developed 
in all specimens, the teeth 5-4 in three specimens, 4 in one; the lateral stripe very distinct. Repre- 
sented by 4 specimens from North Fork Consumne River near Pleasant Valley. The stream is dry in 
its lower course during the summer. 
The third or Alturus form has a long slender body, head and eye of typical size, caudal peduncle 
as deep as in the Pleasant Valley form, lower jaw not so much included as in other forms, and scales 
