232 
BULLETIN OF THE BUREAU OF FISHERIES 
Table 18 . — Clear Lake cisco — Average weight in grams of each age group in each year’s collection, 
and grand average weight for each age group, for the 1931 and the 1932 collections combined, 
together with the annual increment and the percentage increase 
[Sexes separately. Number of specimens in parentheses] 
Age 
Year of capture 
Grand average 
AW 
100AW 
1931 
1932 
W 
Male 
Female 
Male 
Female 
Male 
Female 
Male 
Female 
Male 
Female 
XI .. . 
1, 190 (1) 
1, 190 (1) 
128 
12. 1 
X 
1,035 (1) 
1, 090 (1) 
1, 062 (2) 
-23 
-2.1 
IX 
915 (1) 
880 (1) 
1, 170 (2) 
880 (1) 
1,085 (3) 
84 
135 
10.6 
14.2 
VIII 
760 (3) 
937 (11) 
811 (7) 
969 (8) 
796 (10) 
950 (19) 
67 
33 
9.2 
3.6 
VII 
718 (6) 
859 (17) 
737 (9) 
1,000 (12) 
729 (15) 
917 (29) 
56 
76 
8.3 
9.0 
VI 
687 (7) 
844 (8) 
625 (2) 
820 (1) 
673 (9) 
841 (9) 
26 
71 
4.0 
9.2 
V 
710 (2) 
740 (1) 
629 (7) 
774 (7) 
647 (9) 
770 (8) 
69 
65 
11.9 
9.2 
IV 
603 (5) 
756 (7) 
567 (11) 
680 (14) 
578 (16) 
705 (21) 
160 
175 
38.3 
33.0 
III 
413 (17) 
525 (19) 
422 (23) 
634 (21) 
418 (40) 
530 (40) 
151 
230 
56.6 
77.7 
II 
272 (28) 
303 (27) 
259 (20) 
295 (13) 
267 (48) 
306 (40) 
196 
220 
276. 1 
275. 0 
1 
75 (18) 
88 (15) 
68 (20) 
70 (11) 
71 (38) 
80 (26) 
The weight data are based on fewer specimens than are the length data since 
most of the fish that were preserved for morphometric study were not weighed in the 
field and therefore were not used in these studies. 
Examination of the data bearing on growth in weight reveals how sharply the 
growth of the Clear Lake cisco differs from that in the other three populations (fig. 4). 
The differences that exist among the populations depend upon differences in the 
length-weight relationships in the various populations as well as upon differences 
in the amount of growth in length. The questions of form and changes in form, and 
of the relationship between length and weight are considered in a separate section 
(pp. 237-247.) 
COMPARISON OF THE GROWTH OF THE TROUT LAKE, MUSKELLUNGE 
LAKE, SILVER LAKE, AND CLEAR LAKE CISCO POPULATIONS WITH 
THAT OF CISCO POPULATIONS IN OTHER REGIONS 
Data on the growth of the cisco or lake herring have been published for Lake 
Erie by Clemens (1922), for Oconomowoc and Pine Lakes in southern Wisconsin by 
Cahn (1927), for Lake Huron by Van Oosten (1929), for Lake Ontario by Pritchard 
(1931), for the Indian Village Lakes in northern Indiana by Hile (1931), and for 
Hudson Bay by Dymond (1933). Tables 19 and 20 present a comparison of the 
growth of these populations with that of the populations of the present investigation. 
The lengths (table 19) are expressed in millimeters, the weights (table 20) in grams, 
and the ages in both tables as the number of years of life completed. The methods 
of presentation of the various authors were altered to conform to this uniform method 
of expressing length, weight, and age. Dymond did not include data on growth in 
weight of the Hudson Bay cisco. The largest fish in his collection was a female, 383 
millimeters long and weighed 793 grams. 
