XXXVIil Obituary Notices of Fellows deceased. 
and of period of season on the variation and correlation of the floral parts of 
Lesser:Celandine. 
& 
“Give my love to the Brethren who are co-operating in the matter of 
Celandines, and beseech them to make a better map of their country 
than the enclosed.”—(Oxford, February 23, 1903.) 
Weldon threw his whole energy and love of minute exactitude into the 
task, and his letters are filled with an account of the almost daily changes in 
the type and variability of the Celandine flowers from his selected stations. 
The result of this enquiry was the collection of an immense amount of data 
showing that environment and period in the flowering season affected the 
flower characters to an extent comparable with the differences attributed to 
local races. At Easter of 1903 a series of mishaps prevented the common 
holiday, but this was more than compensated for by the summer vacation. 
The Weldons started with a sea trip to Marseilles and back. They then 
returned to Oxford, in order that work on the article “Crustacea”-for the 
Cambridge Natural History might be carried on, and that an eye might be 
kept on the mice. The data on assortative mating in man collected in the 
previous year were reduced and a joint paper sent to press; the immense 
amount of calculation and reduction involved in the mouse-paper was got 
throuvh ; a joint criticism of Johannsen’s “ Ueber Erblichkeit in Populationen 
und in reinen Linien” was written by the co-editors, under the title 
“ Tnheritance in Phaseolus vulgaris,” and a joint study was made, at Weldon’s 
suggestion, of the relationship between Mendelian formule and the theory of 
ancestral heredity. It was shown that there was no essential antagonism 
between the two methods of approaching the subject, and the results were 
published ultimately at Part XII of the “ Mathematical Contributions to the 
Theory of Evolution,” Weldon persistently declining to allow it to appear as 
a joint memoir, because he had taken no part in certain portions of the more 
complicated algebraic analysis. Christmas found the Weldons in Palermo 
on the snail quest. His letters thence to his co-editor teem with the fresh- 
ness of the sky and the joy of open-air work. 3 
“Out between five and six, in the dark, without any breakfast, 
sunrise up in the hills, a day’s tramp on a piece of bread and a handful 
of olives, and home at seven, laden with snails. Then after dinner 
to clean the beasts. That is not work, and it makes one very fit, but 
one gets tired enough to sleep when the snails are cleaned.” 
At the beginning of 1904 the work on the Brescia Clauwsilia was in 
progress, the mice were multiplying after their kind, and Weldon’s thoughts 
were turning more and more to a determinal theory of inheritance, which 
should give a simple Mendelism at one end of the range and blended 
inheritance at the other. The summer found the Pearsons twelve miles 
from Oxford, at Cogges, near Witney, and the Galtons, twenty miles further, 
at Bibury; there was much cycling to and fro, and the plan of a new book 
