ON THE INHERITANCE OF THE DEFORMITY 
KNOWN AS SPLIT-FOOT OR LOBSTER-CLAW. 
(SECOND PAPER.) 
By GEORGE McMULLAN, M.D. and KARL PEARSON, F.R.S. 
In 1908 Pearson discussed the pedigree of a certain Lobster-Claw or Split-Foot 
Family in this Journal*. Pearson's information was obtained from several 
members of the family, but his photographs and skiagrams were of one particular 
section of it. McMullan, unacquainted with Pearson's paper, read a paper on the 
same family before the Reading Pathological Society in 1910. He worked 
principally with a different section of the family and his photographs and skia- 
grams did not cover the same individuals as Pearson's. Hearing of the latter's 
paper, McMullan placed his material at the disposal of the Editor of this Journal 
and the present supplementary memoir is the result. During the five years that 
have intervened since the first paper several additions have been made by birth to 
the family ; thus while Pearson dealt with 25 deformed individuals the present 
account contains 33 f. Further, somewhat fuller particulars have been found of 
the two earliest generations. The order of birth of Generation III. and further 
the total number of brothers and sisters were given differently by different 
members of the family to Pearson and to McMullan. These discrepancies led 
Pearson to make some investigation into the church registers, but they disclosed 
a rather chaotic state of affairs. Some facts, however, resulted. Ann J. (II. 3) was 
married to Francis 8. (II. 4), at N. in the Chilterns in 1837, both being unable to 
sign their names. It was supposed that III. 2, 3 and 5 were born before the 
S.'s migrated to W. The names of most of the other children in Generation III. 
are to be found at about the proper dates in the baptismal register of W. But 
not until the birth of John S. (III. 13), who must have died under two years of 
* Bimnetriha, Vol. vi. p. 69, 1908. 
t Besides six additional births of deformed children since the date of Pearson's record, IV. 9 has 
recently stated that her parents had two deformed children who died as infants, IV. 4 and IV. 5. The 
statement is now confirmed by IV. 3, 
Biometrika ix 49 
