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the former as "a sort of cross produced by tendencies at 

 once to scrofula and cancer, and that it receives many 

 modifications from peculiarities in the patient's skin, and 

 his morbid tendencies in one or the other direction." Much 

 the same may be said with regard to rodent ulcer, and as to 

 cancer I must refer the reader to what has already been said 

 as to the diathesis of malignant new growths. Xanthelasma 

 is " in part a new growth, and in part a fatty degeneration," 

 depending upon long hereditary descent, and may be 

 regarded as the original offspring of the hepatic diathesis. 



Of the hsemorrhagic division of skin diseases purpura is 

 the only illustration, and it is said to be non-hereditary ; if 

 so, it must be regarded as the exception which proves the 

 rule ! Although it has been asserted that this condition 

 depends upon a morbid alteration in the liquor sanguinis, 

 and that it also involves an affection of the vaso-motor 

 nervous system, as a matter-of-fact nothing definite is known 

 as to its etiology. As to its being the result of a diseased 

 condition of the vascular system, which has also been 

 stated, although evidence of any anatomical alteration in 

 its structure is wanting, " yet there are certain conditions in 

 which a disease of that structure must be presupposed, 

 which exist whenever slight causes give rise to haemorrhages 

 in parts far distant from each other, and which constitute 

 what is known as the hamorrhagic diathesis" l I have 

 elsewhere shown that, according to Mr. Jonathan Hutchinson 

 and others, this diathesis is the result of the long descent of 

 gout; and why, may I ask, should not purpura be the 

 result of the complicated agencies of heredity acting and 

 reacting on human tissues, amid various morbid conditions 

 for an indefinite period, until it is produced in certain 



1 Professor Ernst Schwimmer. 



