GREAT LAKES COREGONIDS 



467 



where in Lake Superior, there would be room for such raciation, but the bloaters seem 

 to be most common along these banks and seldom are found below them. 



Size variations. — In Table 61 five individuals 200 millimeters or longer are 

 compared extensively with five shorter. Below are given values for certain characters 

 for 44 specimens over 200 millimeters in length and 291 smaller ones: 



Pv/P: 



Large specimens, (1.4) 1.7-2 (2.2). 

 Small specimens, (1.4) 1.5-1.8 (2). 

 Av/V: 



Large specimens, (1.1) 1.2-1.4 (1.5). 

 Small specimens, (0.9) 1.1-1.3 (1.6). 



L/H: 



Large specimens, (3.7) 3.9-4.1 (4.3) 

 Small specimens, (3.4) 3.7-4 (4.2). 

 H/E: 



Large specimens, (3.7) 3.9-4 (4.3). 

 Small specimens, (3.2) 3.6-3.8 (4). 



It appears, as is usual, that the head, eye, and paired fins become proportionally 

 shorter with growth. 



Individuals over 130 milfimeters in length usually have been found to be sexually 

 mature. 



COMPARISONS 29 



The characters that separate Jioyi from Tciyi (to which it most nearly approaches) 

 are given on page 443. A discussion of the differences between hoyi and zenithicus is 

 given on page 381, between Jioyi and reighardi on page 411, and between hoyi and 

 nigripinnis on page 427. 



From artedi, hoyi is distinguished chiefly by the fewer gill rakers on the first 

 branchial arch, fewer lateral-line scales, larger head and eye, longer paired fins and 

 maxillary, and by the mandible, which in hoyi is hooked and usually longer than 

 the upper jaw, while in artedi it is seldom hooked and usually equal or shorter. The 

 aforementioned characters, which can be expressed numerically, are compared 

 below : 



Gill rakers on the first branchial arch: 



hoyi, (37) 41-44 (49), with 10 per cent more than 44. 



artedi, (38) 45-48 (53), with 87 per cent more than 44. 

 Lateral-line scales: 



hoyi, (65) 69-78 (84), with 7 per cent more than 78. 



artedi, (72) 84-93 (105), with 92 per cent more than 78. 

 L/H: 



hoyi, (3.4) 3.7-4 (4.3), with 11 per cent more than 4. 

 artedi, (4) 4.2-4.6 (4.8), with 97 per cent more than 4. 

 H/E: 



hoyi, (3.2) 3.6-3.8 (4.3), with 18 per cent more than 3.8. 

 artedi, (3.4) 4-4.2 (4.5), with 84 per cent more than 3.8. 

 H/M: 



hoyi, (2.2) 2.3-2.5 (2.7), with 6 per cent more than 2.5. 

 artedi, (2.5) 2.7-3 (3.2), with 99 per cent more than 2.5. 

 Pv/P: 



hoyi, (1.4) 1.5-1.8 (2.2), with 11 per cent more than 1.8. 

 artedi, (1.6) 1.9-2.2 (2.3), with 74 per cent more than 1.8. 

 Av/V: 



hoyi, (0.9) 1.1-1.3 (1.6), with 10 per cent more than 1.3. 

 artedi, (1.4) 1.5-1.8 (1.9). 



'» Tigures given in this section are based on all collected specimens, except for proportions of artedi, which are'based on speci- 

 mens less than 225 millimeters long. 



