In a paper on alopecia prematura, read before the Colorado State Medical Society three years ago, I referred incidentally to what I believed to be the true cause of hair falling in young men. I desire in this paper to confine myself to the causes alone, and will attempt to show that in most cases the longaccepted theories as to causation are incorrect, and that, in the vast majority of instances, the only hypothesis that will bear the searchlight of investigation is the one that I shall here set forth.
In symptomatic alopecia prematura the causes are various, but easily found. If falling of hair be associated with any visible disease of the scalp or hair, it may safely be regarded as a sequence of the graver disease, and not per se, the disease itself. The variety of alopecia prematura about which we have heretofore known nothing as to its