126 Thirty-fifth Annual Meeting 
trout that fasted 19 days had attained, on October 16, a mean 
weight of 14 grains (or 10 per cent.) heavier than the fish of 
the same species and same original lot that had been fed promptly 
and abundantly, and that each move in the lengthening of the 
fast had been followed by an increase in size. Now without con- 
sideration of any other circumstances than those I have named, 
the conclusion is at once suggested that the fasting was the 
cause of the increased growth. But let us beware of jumping 
at conclusions. Let us see what other circumstances there were 
which may have had a bearing on the case. The different lots of 
trout in the experiment came originally from the same lot of eggs, 
so it is not likely that there could have been any congenital dif- 
ference in capacity for growth. They were reared in water of 
the same origin and the same character in temperature and other 
respects. They received after the fast the same food, administer- 
ed in the same way and, it was supposed, in the same quantity. 
But in one respect there was an important difference in the con- 
ditions to which the different lots were subjected: it was the 
matter of space. The lots of fasting trout were kept in troughs 
uniformly 5 feet long, while the main lots, the control lot among 
them, were in troughs 10 feet long. The survivors of the 19-day 
fasters, only 175 in number at the beginning of October, had 
about 5 square feet of space or 1 square foot for 35 fish. The 
other fasters had much less space, there being more fish to the 
square foot, and the control lot had, during the last part of the 
season, only one square foot of space for 107 fish, and earlier 
were still more crowded. Here, then, is an important advantage 
enjoyed by the subjects of the 19-day fast: they had three or 
four times as much room as the normally treated fish with which 
they were compared, and far more room than any of the trout 
that fasted for shorter periods; and this may account for their 
extraordinary gain in size. 
There is one other point worth considering in this connection. 
It would seem almost inevitable that in the severe ordeal of the 
fasting experiments the fish that would soonest suecumb would 
be the weaklings, and those that would survive the severest tests 
would be those of greatest innate powers of endurance and re- 
cuperation. ‘This may have been another factor of importance 
in bringing about the remarkable results laid before you. And, 
MCR 
