Karl Pearson 
385 
endeavoured to illustrate this in the present paper, by indicating how a want of 
statistical insight has resulted in at least two cases where experiments have been 
interpreted in a sense, which is in no way justified by the observations themselves. 
Regression within the pure line exists in Hydra, and fertility is associated with 
weight in rats. These are far from the only cases in which principles bearing on 
evolution have been propounded on the basis of researches, which prove in fact 
their negation. The biometrician does not desire to waste the energies that may 
be given to better work in personal recriminations with anonymous writers, nor 
in controversy with biologists of repute ; but it is desirable to assert occasionally 
that biometry is very far from moribund, and that biology stands to-day even more 
in need of its methods than it did eight years ago ; for it has now developed theories 
of such complexity, that without the aid of the highest mathematical analysis, it 
is wholly unable to state whether its theories are accurate or not. And this many 
Mendelians admit to-day, and all will have to admit in the very near future. From 
small fragments our Frankenstein has created his soulless monster ; he will need 
all the mathematical aid he can enlist, if his creation is to be brought under control, 
and not to end in destroying him. But I propose to deal further with some 
recent Mendelian developments on another occasion. 
