GREAT LAKES COREGONIDS 



439 



BEEEDING HABITS 



No spawning grounds of the species are known positively, but W. B. Chapin, of 

 Frankfort, Mich., states that during October spawning kiyis are taken in the 70- 

 fathom end of the chub nets that are set on the "northwest shoal," about 12 miles to 

 the northwest of Frankfort. Males taken at Sheboygan, Wis., on October 1, 1920, 

 showed incipient pearl organs, but none of the females had eggs even approaching 

 the ripe state. At Frankfort on October 4, 1920, a few females were nearly ripe, 

 and many showed well-developed eggs. Two pearled males were taken at Michigan 

 City, Ind., on October 11, 1920, and a spent female was found there on November 8, 

 1920, among several females that had not yet spawned. If the fish referred to by 

 Mr. Chapin are kiyis on their spawning grounds, then the fish observed by me at 

 Frankfort were those that had not yet ripened sexually; or there may be a variation 

 of a few weeks in the beginning of the spawning season, as in the case of the core- 

 gonids of the basin, which spawn in shallower water. 



Leucichthys kiyi kiyi of Lake Huron 



The Jciyi of Lake Huron is like the typical form, except that rarely has it been 

 seen so large. In Lake Michigan individuals of 20 to 23 centimeters in length are 

 common, but specimens of such size have been seen rarely in Lake Huron. The 

 principal systematic characters capable of numerical expression are compared below. 



Gill rakers on the first branchial arch : 



Michigan, (34) 36-41 (45)." 



Huron, (34) 36-40 (44) .» 

 Lateral-line scales: 



Michigan, (71) 77-87 (91). 



Huron, (70) 75-83 (89). 

 L/H: 



Michigan, (3.7) 3.8-4.1 (4.3). 

 Huron, (3.5) 3.6-3.9 (4.1). 



H/E: 



Michigan, (3.6) 3.8-4.2 (4.3). 

 Huron, (3.3) 3.6-3.8 (4.3). 

 Pv/P: 



Michigan, (1.1) 1.4-1.7 (2.1). 

 Huron, (1.1) 1.4-1.7 (1.9). 

 Av/V: 



Michigan, (0.96) 1-1.3 (1.4). 

 Huron, (0.93) 1-1.2 (1.4). 



It appears that the scales on the average are less numerous in the lateral line 

 in Huron individuals. The chief difference between the specimens from the two 

 lakes, however, is in the head and eye proportions, but as the Huron specimens are 

 much smaller, on the average, the differences are such as are to be expected and it 

 is likely that in specimens of comparable size they would not exist. (It may be seen 

 in the section on variations that L/H and H/E figures for the few large specimens 

 are very close to the ranges given for these values for the Lake Michigan race, most 

 of which are more than 200 millimeters long.) 



The color in life is not different from that of the Michigan form. Alcoholics 

 show about the same degree of pigmentation, and its distribution also is approxi- 

 mately the same. 



No pearled fish have been seen, but at least the males probably develop pearl 

 organs in the breeding season. 



VARIATIONS 



Virtually all the specimens collected have come from the central basin of the 

 lake, and there is no material for studies of local variation. There are only 16 indi- 



89 These figures are based on an examination of 174 specimens, which range in length from 122 to 245 millimeters. 

 'Figures for Lake Huron are based on an examination of 225 specimens, which range in length from 105 to 249 millimeters. 



