10 
Congenital Anomalies in a Native African Race 
The actual incidence in the two sexes is however greater among females than 
males in the proportion of 5'2 to 3"6 7o- abnormality occurring so fre- 
quently as 45 per mille might almost be cousidered to be a variation within the 
limits of the normal. The fact remains, however, that it is the persistence of 
a foetal character and abnormal, if the whole of mankind be taken into con- 
sideration. 
Dealing more in detail with this defect, there is some variation in the exact 
site of the fistula; the sketches (Fig. 7) serve to illustrate the extremes of posi- 
tion in three directions. 
A B C D E 
Fig. 7. 
Three cases presented two pits on the same side, one each in positions A 
and B. In these three cases the affection was bilateral and symmetrical. The 
common position at which the pit is found is in D. In another case not included 
in the series a pit was observed resembling those above mentioned but situated at 
the junction of the tragus and lobule as in E. 
These helical fistulae, which I have described as little pits, consist of a small 
opening on the skin 1 or 2 mm. in diameter leading into a blind sac 1 or 2 mm. 
deep ; often this sac opens out into a little ampulla which can be seen and felt 
under the skin. The ampulla and canal are generally filled with a little plug of 
sebaceous matter. 
In three cases the skin in this situation looked like scar tissue and presented 
a honey-combed appearance, there being several openings into the ampulla giving 
the impression that an abscess had formed at some past date in the ampulla with 
consequent loss of tissue. 
The fistula is so common and so unremarkable that most tribes have no name 
for it and one cannot elicit long pedigrees to shew its incidence in families. Cases 
of heredity were common enough but the type was not necessarily the same in 
members of the same family ; thus a mother with Left Fistula had a child with 
Right and Left, or again, three brothers were seen two with the Left side affected, 
the third with Right Fistula. 
No malformations in connection with other branchial clefts have been seen. 
