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BULLETIN OF THE BUREAU OF FISHERIES 



wider and more fusiform, in the development of the mandible (which is much frailer 

 in Tciyi), in details of pigmentation, and in the length of the paired fins. The maxil- 

 laries (which usually are immaculate in alpense) are pigmented in Tciyi as a rule, and 

 the latter also has, on the average, more pigment on the premaxillaries, mandible, 

 and abdominal fins than alpense. Comparative values are given: 



Pv/P: 



alpense, (1.6) 1.9-2.2 (2.5), with 89 per cent more than 1.8. 

 kiyi, (1.1) 1.4-1.7 (2.1), with 10 per cent more than 1.8. 

 Av/V: 



alpense, (1.2) 1.4-1.7 (1.9), with 95 per cent more than 1.3. 

 kiyi, (0.96) 1-1.3 (1.4), with 2 per cent more than 1.3. 



Alpense also has a smaller eye, and females of this species will show less developed 

 ova than Tciyi taken at the same time, as Tciyi spawns a month earlier. 



Alpense grows larger than hoyi. The mandible in alpense is heavier and less 

 conspicuously hooked, the head is less sharply triangular (seen from the side), and 

 the maxillary usually is immaculate, while it is always pigmented in Tioyi. In addi- 

 tion, alpense has, on the average, fewer gill rakers on the first branchial arch, more 

 lateral-line scales, a smaller eye, longer snout, and shorter paired fins than the 

 bloater. It spawns in November, while the other spawns in March, so that the 

 state of development of the sex organs may also be a character to separate the forms. 

 Those characters that can be numerically expressed are compared below. The 

 specimens of the two species are not comparable for those characters dealing with 

 proportions, however, as the Tioyi are smaller than the others, so that these differ- 

 ences, which concern proportions, are probably greater than they would be in speci- 

 mens of like size. 



Gill rakers on the first branchial arch: 



alpense, (33) 36-43 (46), with 24 per cent more than 41. 



hoyi, (37) 41-44 (48), with 71 per cent more than 41. 

 Lateral-line scales: 



alpense, (71) 78-85 (96), with 83 per cent more than 77. 



hoyi, (60) 67-77 (84), with 7 per cent more than 77. 

 H/E: 



alpense, (3.8) 4.2-4.6 (5.2), with 81 per cent more than 4.2. 

 hoyi, (3.8) 3.9-4.2 (4.5), with 8 per cent more than 4.2. 



H/S: 



alpense, (3.3) 3.5-3.6 (4), with 13 per cent more than 3.6. 

 hoyi, (3.5) 3.7-3.8 (4.1), with 76 per cent more than 3.6. 

 Pv/P: 



alpense, (1.6) 1.9-2.2 (2.5), with 48 per cent more than 2. 

 hoyi, (1.6) 1.8-2 (2.3), with 21 per cent more than 2. 

 Av/V: 



alpense, (1.2) 1.4-1.7 (1.9), with 54 per cent more than 1.5. 

 hoyi, (1.1) 1.3-1.5 (1.7), with 9 per cent more than 1.5. 



Alpense differs from artedi chiefly in having fewer gill rakers on the first branchial 

 arch, longer ventral fins, head, snout, and maxillary. The figures for these characters- 

 for the two species are given below: 



Gill rakers on the first branchial arch: 



alpense, (33) 36-43 (46), with 6 per cent more than 43. 

 artedi, (41) 46-50 (55), with 97 per cent more than 43. 



