XXX Obituary Notices of Fellows deceased. 
consisted in determining whether the death-rate is correlated with measur- 
able characters of the organism, or, as he himself puts it, “in comparing the 
frequency of abnormalities in young individuals at various stages of growth 
with the frequency of the same abnormalities in adult life, so as to determine 
whether any evidence of selective destruction during growth could be 
discovered or not.” | 
Looking back now on Weldon’s paper of 1894, one realises its great merits : 
it formulated the whole range of problems which must be dealt with 
biometrically before the principle of selection can be raised from hypothesis 
to law. Almost each step of it suggests a mathematical problem of vital ~ 
importance in evolution, which has since been developed at length, or still 
awaits the labour of the ardent biometrician. 
Unfortunately the paper, as well as the suggestive “ Remarks on Variation 
in Animals and Plants” with its memorable words: “The questions raised 
by the Darwinian hypothesis are purely statistical, and the statistical method 
is the only one at present obvious by which that hypothesis can be experi- 
mentally checked,” fell on barren soil. A further instructive report on the 
growth at two moults of a considerable number of crabs was made to the 
Committee in 1897, but appears never to have been published. Later, an 
account of work on Natural Selection in crabs was given by Weldon in his 
Presidential Address to the Zoological Section of the British Association, 
Bristol, 1898. In the paper just mentioned, after several years of discourage- 
ment and much hard labour, he succeeded in demonstrating that natural 
selection was really at work, and further that it was at work at a very 
sensible rate. The labour involved was excessive. One “crabbery ” consisted 
of 500 wide-mouthed bottles, each with two syphons for a constant flow of 
sea water. Each crab had to be fed daily and its bottle cleaned. But in 
the autumn a rest came. The British Association Address was written and 
Weldon thoroughly enjoyed his presidency of Section D at Bristol. 
It may not be out of place here to note the great aid Weldon’s artistic 
instinct and literary training gave to his scientific expression. His papers 
are models of clear exposition, his facts are well marshalled, his phraseology 
apt, his arguments concise, and his conclusions tersely and definitely 
expressed. The result, however, was not reached without much labour. 
There was never any artificial briluancy introduced in the process; rhetoric 
in the service of science was intolerable to Weldon. His was simply an 
attempt to choose the suitable form and the right words for a given purpose. 
It was comparable with his sense of sound, with his extraordinary gift of 
appreciating and reproducing the exact intonation of a foreign tongue. 
Considerable changes were soon to take place in his environment and 
scheme of work. Lankester had been appointed Director to the British 
Museum (Natural History), and in February, 1899, Weldon succeeded him in 
the Linacre Professorship at Oxford. In the February of 1897 the Royal 
Society Evolution Committee received a large increase of membership; it 
ceased henceforth to “conduct statistical mquiries into the measurable 
