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IOWA ACADEMY OF SCIENCE Vor.. XXVII, 1920 
44° C. (Fig. 53, A-A' and B-B'). Those individuals which had 
three definite maxima were averaged, and numbered eleven (Fig. 
54, 11-11). The first maximum was at — 1°C., the second at 
— 3°C. and the third at 36° C. Rigor caloris began at 42° C. 
Nine, the remainder of the twenty experiments, fell into the 
two-maxima class (Fig. 54, 9-9). The first maximum appeared 
at — 2°C. and the other at 36° C. Rigor caloris began at 44° C. 
A typical two-maxima curve (22-22) and a typical three-maxima 
(10-10) curve are shown in Fig. 55. Here, as in the former, 
Fig. 54. Combined Mean Three-maxima and Two-maxima Curves. 
11-11 represents a mean three-maxima curve which was plotted from the mean 
maxima and minima of the eleven which fell in this class. 
9-9 represents a mean two-maxima curve which was plotted from the mean maxima 
and minima of the nine which fell in this class. 
the first maximum appeared at — 2°C. and the other at 38 °C., 
while in the latter the first maximum is at — 3°C., the second at 
— 3°C. and the third at 40° C. Rigor caloris for (22-22) began 
at 41°C. and for (10-10) at 43°C. 
The range of the first maxima for all curves was from — 1° 
to — 3°C. and fell in the first period. For the second maxima 
of all curves — 3° to — 2°C. was the limit and fell in the second 
period. The third maxima came from 36° to 40° C. and fell in 
the third period. Rigor caloris began from 41° to 44°C. and 
its maxima was from 48° to 50° C. 
Rigor caloris maximum generally proximated the greatest maxi- 
ma but when all were averaged it was slightly less than the 
greatest maximum. The greatest maximum measured 6.9 cen- 
timeters and that of rigor 6.6. In the individual cases, out of the 
