GREAT LAKES COREGONIDS 



445 



does not necessarily occur everywhere at depths of more than 40 or even 60 fathoms, 

 but for the present we may say that during the year the species ranges between the 

 depths of 40 and 100 fathoms. As no Tciyi occurred in the shallow-water sets that 

 took Tioyi, the inshore limit of their range, at least when not spawning, probably 

 may be set around 40 fathoms. There are no data to fix the maximum depths which 

 the species frequents. 



RELATIVE ABUNDANCE 



As, on account of its small size, Tciyi has no commercial importance, it is not fished 

 for, and its abundance can only be determined relative to that of hoyi, which is like 

 it in respect to size and usefulness. Except possibly in the lifts made in late November 

 and early December, 1922 (records 5 and 6), when the species was spawning, Tciyi 

 never has been anything but rare in the inspected catches; and except for the records 

 made off Marquette, Mich., Apostle Islands, Wis., and Coppermine Point, Ontario 

 (records 3, 9, 10, and 11), all of them from nets extending into 40 fathoms, it never 

 has been taken in company with Tioyi. On these four occasions only stray specimens 

 were found entangled with the latter. 



BREEDING HABITS 



Specimens collected as late as October 3, 1917, off Grand Marais, Mich., were 

 not yet ripe, although females taken on this date showed eggs approaching the ripe 

 state. Of 13 specimens received from off Marquette, Mich., on November 22, 1922, 

 9 were males from which milt could be forced and the 4 females had eggs nearly ripe. 

 Of the 39 fish received from the same source on December 5, 1922, only 6 were males, 

 and of the 33 females the majority were spawning or spent. These data indicate that 

 the spawning season falls in late November or early December. 



Unfortunately there have been no exact localities recorded for these spawning 

 fish taken off Marquette, but Prof. J. N. Lowe, of the Northern Normal School, who 

 sent the specimens, states that they were taken off Granite Island, probably in 70 

 fathoms. This information then fixes at least one spawning ground for the species 

 in the lake, and doubtless there are others. 



Leucichthys kiyi orientalis (new subspecies) of Lake Ontario 



The Tciyi of Lake Ontario attains about the same maximum size as the typical 

 form, except that in virgin waters extreme examples measured 250 millimeters and 

 a single specimen of 263 millimeters was seen. The general appearance of the two 

 forms is the same, but the Ontario representative differs rather markedly in several 

 characters. Values for certain of these are compared below: 



Gill rakers on the first branchial arch: 

 Michigan, (34) 36-41 (45). • 

 Ontario, (41) 43-46 (48) . 10 



Lateral-line scales: 



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

 Ontario, (71) 76-87 (91). 



L/H: 



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

 Ontario, (3.8) 4.1-4.2 (4.4). 



H/E: 



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

 Ontario, (3.6) 3.9-4.2 (4.4). 

 Pv/P: 



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

 Ontario, (1.5) 1.7-2 (2.2). 

 Av/V: 



Michigan, (0.9) 1-1.3 (1.4). 

 Ontario, (1) 1.2-1.4 (1.6). 



• These and succeeding figures are based on an examination of 174 specimens ranging in length from 122 to 245 millimeters. 

 » These and succeeding figures for Lake Ontario are based on an examination of 135 specimens ranging in length from 148 to 

 263 millimeters. 



