will recall the fact that they were often "bilious" in their youth; which "biliousness" turns out to have been regularly preceded by one-sided headache, and to have been severe in proportion to the severity and duration of that previous headache. I ask the reader to dwell with fixed attention on this fact of the exclusiveness, or almost exclusiveness, with which the neuralgias of the anterior part of the head are represented during the period of bodily development, and especially in the years just succeeding puberty, by migraine or by clavus. When this fact has thoroughly entered the mind, we can hardly help joining with it that other and most important fact already noticed, of the close connection between the predisposition to migraine and the predisposition to epilepsy, and reflecting further on the strong tendency which epilepsy likewise shows to infest the earlier years of sexual life. In view of these things, it is difficult to avoid the inference that both the epileptic and the neuralgic affections of this critical period of life are the expression of a morbid condition of the medulla oblongata, in which the sensory root of the trigeminus has its origin; and further, that this morbid condition (tending to explosive and atactic manifestations of nerve-force) must have its basis in defective nutrition. For, be it remembered, the epoch of sexual development is one in which an enormous addition is being made to the expenditure of vital energy; besides the continuous processes of the growth of the tissues and organs generally, the sexual apparatus, with its nervous supply, is making by its development heavy demands upon the nutritive powers of the organism; and, it is scarcely possible but that portions of the nervous centres, not directly connected with it, should proportionally suffer in their nutrition, probably through defective blood-supply. When we add to this the abnormal strain that is being put on the brain, in many cases, by a forcing plan of mental education, we shall perceive a source not merely of exhaustive expenditure of nervous power, but of secondary irritation of centres like the medulla oblongata, that are probably already somewhat lowered in power of vital resistance, and proportionably irritable. Let us suppose, then, that to all these unfavorable conditions there was added the circumstance that the structure of the medulla oblongata, or of parts of it, was congenitally weak and imperfect; then surely it would be scarcely possible for these loci minimæ resistentiæ to escape being thrown into that state of weak and disorderly commotion which eminently favors pain in the sensory, and convulsion in the motor apparatus.