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nutritive condition of the soil or material in which the 

 fungus develops, or upon some special state of the general 

 health or constitution. In fact, the state of the soil is a most 

 important condition, and the rapidity with which a small 

 spot of ringworm will spread before it comes under efficient 

 treatment, depends chiefly upon the peculiar and unknown 

 condition of the soil or nidus." In seeking to account for 

 this " unknown condition," whether of the nature of pre- 

 disposition or insusceptibility, I maintain that it depends 

 upon idiosyncratic peculiarity in the structure of the infected 

 parts, which, like all other idiosyncratic conditions, has 

 been transmitted hereditarily. Having already discussed the 

 idiosyncrasies of structure represented by certain inherited 

 proclivities of tissue, I need not refer to them here in any 

 detail further than to state that they account for those pre- 

 dispositions and insusceptibilities referred to above by Dr. 

 Alder Smith, and are very frequently the primary causes of 

 :such skin diseases as icthyosis, psoriasis, xanthelasma, 

 molluscum fibrosum, etc., and probably also of " steatomata 

 of the scalp, lipomata, adenomatous tumours in the breast, 

 multiple uterine fibroids, milium, whether on the face or 

 elsewhere, and a host of others." l 



As illustrating further, and more forcibly, the inherited 

 proclivities of the integument I may here refer to the 

 various forms of acne, which undoubtedly denote original 

 and heritable peculiarity in the structure of the skin. As 

 Mr. Hutchinson says : " The location of acne on the face 

 is probably often explained by pre-existing peculiarities in 

 the state of the skin of the face . . . Acne is very constantly 

 hereditary, the same form often prevailing in several members 

 of a family, and acne tuberosa, I believe, often descends 



1 Hutchinson. 



