(b) As to personal habits: overwork, masturbation, the abuse of tobacco, alcohol, or coitus, injudicious diet, abnormal postures, injurious avocations, etc.

(c) As to dyscrasic and hæmic conditions: uræmia, lithæmia, anæmia, malarial and syphilitic infection, etc.

(d) As to the condition of important organs: of the eye in connection with headaches and vertigo; of the ear in relation to vertigo and epileptiform attacks; of the heart (and arterial tension) in various head-symptoms; of the sexual organs in hysteria, hypochondriasis, epilepsy, etc.

A serious stumbling-block in this last line of inquiry is the ever-recurring question as to the causal relation between the symptoms observed. Is the asthenopia the cause of the headache, or does the neurasthenia, giving rise to the headache, cause the asthenopia? Does the extremely slow action of the heart in a given case produce the epileptoid attacks, or are both due to a lesion of the medulla? Does ovarian hyperæsthesia and neuralgia (with or without organic changes) cause the hystero-epilepsy, or is the ovaria one of the numerous peripherally projected sensory symptoms of the hysteric state? Does the lithæmia, oxaluria, azoturia, or phosphaturia found in a patient give rise to the nervous symptoms complained of, or are they (the morbid excretions) the result of defective innervation? The candid neurologist, looking at his cases from the standpoint of the general physician rather than from the loophole of narrow specialism, must admit that these questions vex him daily, and that they are often not to be resolved in the present state of knowledge except by a recurrence to the therapeutic test.

For this extremely difficult diagnosis of the pathology of functional nervous affections we would obtain much immediate assistance if observers had the courage to publish their cases in continuous series, instead of giving us successful cases, which often only serve to mislead. For example, how greatly would the question of the relation between ovarian symptoms and epilepsy (also hystero-epilepsy) be advanced if we had the final results of all cases of removal of the ovaries for these diseases at a period not less than one year after the operation! And so with the attempts made to cure headaches by the correction of errors of refraction and weakness of the interni. The profession has a right to demand a frank and full report of the experience of those who practice and teach in these directions.

THE LOCALIZATION OF LESIONS IN THE NERVOUS SYSTEM.

BY E. C. SEGUIN, M.D.