200 
A Piebald Family 
a dark-haired boy and a light-haired girl. A girl, IV. 19, was born next and she 
had twin sons, V. 15 and 16, who were also normal. The last three children, 
IV. 20 — 22, a girl, a boy, and one whose sex I am unable to ascertain, were all 
normally pigmented and all died at a very early age. 
The pedigree confirms the strongly hereditary nature of piebaldism, and in this 
as in other published cases the character can affect either sex, but has only been 
transmitted by those affected. Unless we are to assume that in the case of such 
a rare anomaly as piebaldism, I. 2, II. 2 or III. 1, were really unnoticed piebalds, 
then III. 2 could only be heterozygous, or since piebaldism is dominant a (DR). 
We must take IV. 4, IV. 9, IV. 11 and V. 7 for pure recessives (BR). Thus the 
number of i^iebalds in the five sibships of generations IV, V and VI should be one 
quarter, i.e. J (15 + 3 -I- 1 -h 6 -h 2) = 7 nearly. We have actually 14 out of 27, 
thus piebaldism does not seem to act numerically as a pure dominant. 
The areas of unpigmented skin are less than in the classical piebalds, but it is 
probable that in some, at least, they are larger and more numerous than I have 
stated. On the covered parts of the body and legs, which I was unable to 
examine except in the baby, they would not be very noticeable. It was not until 
I had noticed the white skin on the neck and arras of one of them that I was told 
anything about the existence of similar patches on the others. If true, it is 
remarkable that none have had white patches on the legs. 
With regard to the local distribution of the pigment, there appears to be an 
excess at the edges of some of the unpigmented areas, as has been noted in other 
cases. In the case of other pale areas, the demarcation between them and the 
normal skin is very slight, and is probably due to the fact that they are not wholly 
unpigmented. This i-emark applies especially to the forehead, which in some of 
them looks paler than natural, but not wholly devoid of pigment. 
In some the eyelashes are alternately white and brown, and in others the eye- 
brows are similar, and in one at least hairs growing on the scalp near the blaze 
are in some instances entirely without either diffused or granular pigment. This 
suggests that the skin beneath may show a deficient and irregular distribution of 
pigment. 
The most interesting feature is the occurrence in three members of the family 
of well-marked heterochromia iridis, a character which has been met with in 
members of a piebald family, but always independently of their piebaldism, never, 
as in this case, in true association with it. It proves conclusively that these cases 
are not congenital leucoderma. 
There seems to be no association of piebaldism and general lack of pigmenta- 
tion of hair and irides. Affected and unaffected members have been both fair and 
dark, but the fairest piebalds seem to have the most extensive frontal blazes. 
In the cases photographed the individuals were blonds and there has been great 
difficulty in getting a good photographic contrast of differences of pigmentation 
very noticeable in the living subject. 
