The disease entity known as myasthenia gravis was first described by Willis1 in the seventeenth century. Although this condition is relatively easy to recognize clinically, its cause has remained obscure. Pathologically in many cases there are variable degrees of nonspecific degenerative muscle atrophy. In more than 50 per cent of cases focal collections of small round cells have been observed in muscles and other organs. These small foci of cells have been termed "lymphorrhages" and when present are diagnostically significant. A relatively large number of cases have been reported in which thymic neoplasms existed. The conspicuous symptomatic features of myasthenia gravis are excessively rapid fatigability of muscles in action and quick restitution of function on relaxation. The muscular exhaustibility may be elicited in the form of a characteristic electrical reaction which has been termed the Jolly reaction.
In this article no effort will be made to discuss in detail