The ease with which it is possible to make a diagnosis of tuberculosis in an otherwise obscure ocular lesion probably accounts for the vast literature accumulated on this subject since Pirquet first called attention to his now famous skin reactions. In years gone by, a group of symptoms of which the etiology was unknown was referred to clinically as an idiopathic disease. The terms idiopathic, scrofulous and strumous, and the various diatheses are no longer encountered with the same degree of frequency in the literature. Instead, there is an assortment of skin reactions for this, that or the other form of protein, specific or nonspecific, which possess the added aura of laboratory prestige and its consequent impressiveness. That a patient may for many years show a positive Widal reaction is no reason for attributing every obscure symptom or lesion to his previous typhoid infection, and the same may be