Intercostal neuralgia not unfrequently accompanies, and is sometimes a valuable indication of, phthisis. I do not mean to say that the vague pains in the chest-walls, which are so very common in phthisis, are to be indiscriminately accounted neuralgia; on the contrary, they are, in the large majority of instances, merely myalgic, and arise from the participation of the pectorals, or intercostals, or both, in the mal-nutrition which prevails in the organism generally. But it happens, sometimes that a distinctly intermitting neuralgia occurs as an early symptom of phthisis; in fact, where there is a predisposition to neurotic affections, I believe that this is not very uncommon. The subjects are generally women; they are mostly of that class of phthisical patients who have a quick intelligence, fine soft hair, and a sanguine temperament. I have had one male patient under my care: this was a young gentleman aged eighteen, in whom a neuralgic access came on with so much severity, and caused so much constitutional disturbance, that the idea of pleurisy was strongly suggested. The paroxysms returned at irregular intervals for a considerable period: they were quite unlike myalgic pains, not only in their character, but more especially with respect to the circumstances which were found to provoke their recurrence. They were the first symptoms which lead to any careful examination of the chest; it was then found that there were prolonged expiration and slight dulness, at one apex. At this period, wasting had not seriously commenced; but, on the other hand, there was an extraordinary degree of debility for so early a stage of phthisis. I am inclined to think that self-abuse was the principal cause both of the phthisis and the neuralgia, acting doubtless on a predisposed organism, for his family was rather specially beset with tendencies to consumption. I may add here, that it has appeared to me that young persons with phthisical tendencies are specially liable to neuralgic affections as a consequence of self-abuse.