GREAT LAKES COREGONIDS 



415 



Pv/P: 



reighardi, (1.7) 2.2-2.5 (2.9), with 89 per cent more than 2.1. 

 hoyi, (1.4) 1.7-2 (2.2), with 1 per cent more than 2.1. 

 kiyi, (1.5) 1.7-2 (2.2), with 3 per cent more than 2.1. 

 artedi, (1.7) 1.9-2.1 (2.5), with 15 per cent more than 2.1. 

 Av/V: 



reighardi, (1.3) 1.5-1.7 (2.1), with 90 per cent more than 1.4. 

 hoyi, (1.1) 1.3-1.5 (1.6), with 38 per cent more than 1.4. 

 kiyi, (1) 1.2-1.4 (1.6), with 7 per cent more than 1.4. 

 artedi, (1.3) 1.5-1.8 (2), with 89 per cent more than 1.4. 



Reighardi also has a less triangular head, seen from the side, a wider, more terete 

 body, and the mandible is almost always shorter than the upper jaw, while in the 

 other species, excepting artedi the reverse is true. In artedi the lower jaw has been 

 found shorter than the upper in less than half the specimens examined. The body 

 outline, as seen from the side, is more elliptical than in Tciyi; and reighardi has also 

 a shorter head, larger eye, and longer maxillary and snout than this species. It has 

 a shorter head and maxillary than hoyi. As reighardi spawns in spring (probably in 

 April or May) and Tciyi spawns in August and artedi in November, the state of develop- 

 ment of the sex organs may, at certain seasons, at least, aid in separating individual? 

 of the several species. 



GEOGRAPHICAL DISTRIBUTION 



Data on the occurrence of reighardi given in Table 38 and shown platted on the 

 chart in Figure 7 show that specimens of the species have been taken in the special 

 2^2 an d 2^-inch nets out of every port visited on the New York shore and out of 

 Brighton on the Canadian shore. Specimens have been seen also from other collec- 

 tions taken from off Port Credit, Ontario. It is probable, then, that the species is 

 distributed along the shores of the entire lake. 



BATHYMETRIC DISTRIBUTION 



The only data available on the depth distribution of the species are derived from 

 the use of special nets of 2^2 and 2%-inch mesh, which were set only between the 

 depths of 20 and 75 fathoms at some time during the summers of 1921 and 1923, 

 and from the examination of a few sets of 3-inch nets that are in commercial use for 

 herring. Individuals occurred in the catches of these nets at depths of 20 to 65 

 fathoms. They were absent in the lift off Oswego, N. Y., made on September 4, 

 1923, in 70 to 75 fathoms, but occurred in lifts from off that port made in shallower 

 water. 



RELATIVE ABUNDANCE 



The data from any of the nets show nothing conclusive about the relative abund- 

 ance of the species, inasmuch as all the special sets were made with only the element 

 of depth as a guiding factor, and it is well known that other factors influence the dis- 

 tribution of fishes. The data, however, seem to point to certain conclusions, which 

 may be given more weight in that they agree with what is known about the habits 

 of the species elsewhere. 



No reighardi were taken in a special lift made off Bronte, Ontario, on June 29, 

 1921, in 40 to 50 fathoms; off Wilson, N. Y., on June 25, 1921, and July 16, 1921, in 

 50 fathoms, and off Oswego, N. Y., on September, 4, 1923, in 70 to 75 fathoms. 

 Specimens of the species were rare in a lift made 8}^ miles NNW. of Sodus Point, 



