342 Anomalies of Pigmentation among Natives of Nyasaland 
When he smiles the subject has a retracted everted upper lip with fold of 
mucous membrane showing beneath it ; the upper lip has a central linear 
depression instead of being pointed. 
In reporting the case of Ng'ombe (B 4) it was pointed out that pigment spots 
hardly occurred apart from pitting and that the pitting might be the result of 
ulceration with scarring. In the present case, however, no history of such loss of 
substance could be elicited, yet a similar condition obtained. Both these cases 
are adults, whereas my other cases of spotted albinism are children in whom the 
pigmented areas are not depressed. Will these children develop depressed areas ? 
I think they very possibly will. I believe that localised changes in the skin occur 
and cause the depressed areas, the pigmentation occurring before or at the same 
time, but whereas the pigmentation is visible in childhood the early results of 
depression are not seen. The irides of this man are a light brown, that is to say, 
more pigmented than in Ng'ombe, who only had an orange peri-pupillary ring. 
This case is included in Class II, though the iris colour makes it an intermediate 
type. A portion of skin including in its centre one of the pigmented spots was 
excised from the arm of this case and preserved*. Vertical sections were cut and 
examined microscopically stained and unstained and except for the complete 
absence of pigment granules the leucotic skin as a whole appeared in no way to 
depart from the normal. The several layers of the epidermis were not very thick, 
the dermal papillae and processes of epidermis between them being little developed 
but regular. 
The structure of the skin at the site of the pigmented spot (freckle ?) differed, 
however, very considerably. Here the dermal papillae are irregularly prolonged 
towards the surface so that the epidermal processes appear much longer but the 
rest of the epidermis thinner. The condition might be considered to resemble a 
wart which was "in " the skin and not "raised" above the surface. 
Pigment granules were seen to occur in all the layers of the epidermis, most 
numerous in the cells of the downward processes of the epidermis, especially in the 
basal layer of these cells, which envelop the dermal papillae. They were seen to 
be more abundant in the peripheral parts of the cells and most densely packed at 
the deeper poles of the cells. 
The granules were of a brown colour and where massed, appear as a homo- 
geneous black mass. 
In the subjacent dermis some cells were seen to contain pigment granules, 
they were few in number and the number of contained granules was small. 
Passing from the middle of the pigment patch where the aggregation of granules 
was greatest, they diminish in number as the periphery is reached. The dimi- 
nution in the amount of pigment was seen to be gradual to one side of the 
section, the gradation taking place over several millimetres with some isolated 
* See Plate XVII (21) and (22) for microphotographs of albinotic skin and " freckle." 
