AGE AND GROWTH OF THE CISCO 
245 
Table 31 . — Clear Lake ciscoes — Values of length, theoretical weight, actual weight, and K at 10- 
millimeter length intervals 
1931, male 
1931, female 
Length 
Calcu- 
lated 
weight 
Actual 
weight 
K 
Length 
Calcu- 
lated 
weight 
Actual 
weight 
K 
167 
62 
68 
1.47 
177. 
73 
76 
1.38 
174 
72 
70 
1.37 
183 
83 
85 
1.36 
182 
84 
80 
1.34 
197 
108 
106 
1.39 
203 
124 
124 
1.48 
201 
116 
122 
1.51 
234... 
204 
195 
1.53 
231 
193 
184 
1.49 
246.... 
241 
240 
1.62 
244 
237 
226 
1.54 
253 
268 
272 
1.67 
256 
280 
284 
1.69 
265 
31G 
316 
1.70 
266 
321 
312 
1.68 
273 
351 
330 
1.62 
275 
365 
352 
1.69 
282 
392 
385 
1.71 
283 
406 
385 
1.69 
293 . 
448 
445 
1.77 
296 
480 
462 
1.77 
301 
493 
465 
1.71 
303 
522 
546 
1.96 
316 
582 
595 
1.89 
314 
589 
570 
1.84 
322 
624 
663 
1.99 
327. 
686 
712 
2. 05 
333 
700 
708 
1.92 
335 
752 
766 
2.04 
343 
777 
803 
2.00 
345 
833 
866 
2.07 
350 
834 
850 
1.98 
353 
905 
933 
2. 12 
362 
997 
1,036 
2. 18 
371. 
1,088 
1,048 
2.05 
1932, male 
1932, female 
Length 
Calcu- 
lated 
weight 
Actual 
weight 
K 
Length 
Calcu- 
lated 
weight 
Actual 
weight 
K 
168 
57 
59 
1. 26 
155 
42 
43 
1. 13 
176 
69 
68 
1.24 
175 
68 
68 
1.26 
183--. 
79 
79 
1. 29 
180 
76 
75 
1.29 
215 
141 
138 
1.39 
195. 
106 
100 
1.43 
234 
192 
182 
1.42 
255 
268 
268 
1.62 
245 
227 
226 
1.53 
265 
314 
309 
1. 69 
255 
262 
244 
1.47 
274 
338 
351 
1.64 
264 
297 
292 
1.53 
290. 
394 
433 
1.62 
273 
335 
370 
1.82 
306- 
520 
529 
1.81 
288 
407 
434 
1.75 
315 
694 
588 
1.90 
294 
437 
443 
1.85 
324 
695 
650 
2.05 
302 
484 
508 
1.80 
334 
704 
724 
1.90 
315. 
565 
563 
1.90 
345 
812 
821 
1.98 
326 
634 
657 
1.90 
356 
984 
923 
2. 18 
334 
695 
708 
1.91 
365 
1,002 
1,012 
2. 06 
343 
767 
773 
1.92 
373 
1, 107 
1,091 
2. 12 
352 
847 
840 
1.82 
384 
1,198 
1,212 
2. 12 
365 
960 
885 
1.79 
The comparisons of theoretical and actual weights show that the equations of 
table 27 fit the observed data in a quite satisfactory manner, for in general the agree- 
ment between actual and calculated weights is good. The discrepancies between 
actual and calculated weights are greater in the Clear Lake samples (table 31) than 
in those of the other three lakes. This might be expected not only because of the 
smaller numbers of fish in the Clear Lake collections but also because of the much 
greater size range shown by the ciscoes of this lake. 
The equations themselves (table 27) contribute interesting information relative to 
the problem discussed previously (pp. 238-242) concerning the use of C as a coefficient 
of condition. The examination of the values taken by CX 10 5 shows how widely this 
quantity can vary not only within different populations of the same species but also 
in different sexes and in different years’ collections of the same population. Certainly 
the value 0.03652 (Clear Lake females, 1932) cannot be compared directly as a 
measure of condition with the value 4,568.9 (Muskellunge Lake, 1928), particularly 
in view of the fact that the higher value of C pertains to the slenderer form. Nor 
can the higher values of C shown by the males in the Clear Lake equations be inter- 
preted as showing the males of this population to be in better condition than the 
females. The actual values of K and of weight for length show that the reverse is 
true. The table shows yet other examples that demonstrate clearly that values of C 
cannot be compared either between the sexes or between different years’ collections 
of the same population, much less between different populations. 
If the variations in the value of C are examined in relation to variations in the 
values of the exponents, m and n, it may be seen again that the values taken by C 
depend on the values taken by n. If n is high, C is small — and the reverse. Thus 
it may be seen that here as in Jarvi’s data the values of C do not depend on relative 
heaviness but on the rate of change in relative heaviness as measured by the expo- 
nents, m and n. 
The examination of the values taken by n show further that this quantity is not 
fixed either for a species or a population. The values of the exponent not only vary 
tremendously from lake to lake but also vary considerably from year to year in the 
