the brain. The animals chosen were dogs, rabbits, cats, monkeys, etc.; and the result has been, that these experimenters have found that there is a central portion of the brain that can be made to respond to these excitements. These portions correspond very nearly in all the animals on which the experiments have been tried.

19. Three Different Regions of the Brain.

They have found that there is a region in the forehead from which they get no response. This, in man, may be indicated by a line passing from the lower edge of the eye-sockets, up and backwards to the top of the head at a point a short distance before what is known as the crown of the head. This part of the brain is exceedingly small in animals. Even in the highest of the monkeys it is inconsiderable, compared with its size in man. And as the only responses which these gentlemen have been able to secure are motion, the result of muscular contraction and not mere thought or volition, or any proof of such mental acts, we are left to suppose that, in accordance with the doctrines of Gall and the phrenologists, as well as in fact the common belief of mankind, this part of the brain is specially occupied with the purely mental and rational functions of thought and reasoning.

These experimenters have found another region in the back part of the head, extending nearly in a direct line from the crown of the head down to the cerebellum, inclining rather backwards than perpendicularly down, from which they can get no response. In a few instances, Ferrier succeeded in removing all the cortical portion of the brain from this region, and keeping the animal alive. The most noted effect was the loss of appetite; no relish for food and no inclination to take any, having been manifested by the animal. It would eat, however, if food were put into its mouth.

No perceptible effects of any kind, however, followed-in

animals-from the removal of the frontal lobes of the brain But in regard to the foccipital lobes, he says, (p. 194), that when they are removed "the appetite for food is abolished, the "animals refusing that which they formerly exhibited great ' liking for. This I have tested in various animals and in "various ways. The appetite for drink, however, still remained; for nearly all the subjects of my experiments took "water offered them, or found it for themselves, when they "could not be prevailed upon to eat." In one case the animal totally recovered after the operation. Of this one he says, "The refusal of food continued for five days, the animal hav"ing only sucked a piece of orange or two, which it accepted, refusing all its former dishes. During the above period it "used to run about with a companion monkey, of which it "had constituted itself protector, and exhibited unmistakable "signs of anger when any one else touched it. At the end of "the fifth day, after trying to tempt it with various kinds of "food, I offered it a cold potato. This it took, smelt several "times, and at last, as if struck by a new idea, it began to eat "with great relish. From this time it began to take food reg"ularly and recovered. As to the animal's mental condition, "only some degree of apathy and general indifference was ob"served, it having been formerly a very lively and intelligent "monkey."

20. Supposed Functions of the Occipital Lobes.

Ferrier adds some other remarks, (pp. 195, 196), with regard to the functions of the posterior portion of the hemispheres which are worth considering. "The organic, or viseral "sensations form a group distinct from the tactile or cutane"C ous. This is shown, etc. . . As a general rule the states "of the viscera do not rise into distinct consciousness, except "when the condition is extremely abnormal, or in inflammatory affections. In such cases, the pain may be more or less

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"accurately referred to the viscous affected, but more generally "the morbid states of the viscera express themselves, through "other sensory nerves, often at a distance from the seat of the "malady. . . Thus abnormal states of stomach and intes-. "tines show themselves in neurosis of the fifth pair, as in "headache, toothache, and the like."

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'But," he continues, "though the visecra except in extreme "conditions of disease, have no definite expression in con"sciousness, they form the chief foundation, according as they

are healthy and vigorous, or depressed and morbid, of that "indefinable and non-localisable feeling of joyousness or de"pression with which everyone is familiar."

The general inference from these experiments and observations is, that as the forehead is the seat of intelligence and the rational sensibilities. so the hindhead is the seat of the animal appetites, and the instincts, of the more amiabte kind. This should be distinctly noted for those of the more selfish and irascible character, depend upon other considerations, as do also perhaps the lower and more purely animal appetites. The hindhead is the seat of the good-natured affections and instincts, rather than of either the lower and baser passions, or the higher and more heroic sentiments.

21. Reactions of the Middle Lobes.

Between the two tracts thus indicated, Ferrier seems to have succeeded in connecting the gray matter of the cortical covering -perhaps with the two classes of reflex actions already indicated. By applying the stimulant in one place, the animal would move one leg-by applying it in another, motion in another leg or some other limb, would be the result. At other places the stimulus seemed to affect one or another of the organs of special sense, as the eye or the ear.

But it is a very significant fact, as Ferrier admits, (p. 136), that "after removal of the gray matter of the cortex, in regions

"from which distinct localized movements could be excited'they found that the application of the electrodes to the medullary 'fibres, caused the same definite action as before. The only difference being, according to Corville and Duret, that the current re"" Iquires to be intensified."

I have italicised the few last words, because they seem to me to point to an interpretation of the experiments entirely different from the one usually given. Or, at least, they seem to throw grave doubt over it. With this fact before us, it seems to me that we are precluded from inferring that the gray matter of the brain in that region exerts any such reactionary character as these gentlemen have ascribed to it. It thus throws doubt upon all inferences with regard to "the localization of "special faculties." It shows, indeed, that the nerve-fibres from the various parts of the body do pass through the sensorium up into the interior of the hemispheres, and becomethat is the efferent fibres, become-the conduits of the brain's influence, and the mind's influence through the brain, to the various parts of the body, with which they are connected. But they certainly leave room for the supposition that after all, the gray matter of the brain, just over their ends, has nothing more to do with the motions which they produce, than any other part of the brain whatever.

It should be added, however, that Ferrier has carefully considered this view of the matter, and does not accept it. He has given, indeed, facts and reasons of a very weighty character why it should not be adopted. This line of investigation, however, is but in its infancy, and is being prosecuted by more than one eager and very competent inquirer. Any day there may come the announcement of new discoveries or of a new interpretation of facts already known, which will put the whole matter in an entirely new light. This is, in fact, one of the interesting points, not to call them difficulties, of our Science, that there may at any time occur, and there are in fact, constantly occuring, discoveries of fact that call for quite an exten

sive revision of what we had before held as probable conjecture if not as established truth.

I shall present another view of these cerebral reactions, after I have discussed the various kinds of reflex action far enough to prepare the way for its acceptance. (Lect. IX, § 16. Lect. XII, § 20.)

22. Danger of Wrong Inferences from the Snpposed Analogy of Man and Animals.

There is, however, one feature of these experiments that is too important to be overlooked, and one, too, which greatly affects their value. The subjects on which they were performed were all dumb animals, animals that could not speak and describe the effects of the electrization, as they appeared internally to the animal itself. From the nature of the case no such experiments are likely to be performed on human beings, and we must content ourselves, therefore, with what we can learn from them by the purely physiological method. If it were possible to apply this method to human beings, without destroying at the same time the consciousness of the patient, we should undoubtedly be able to ascertain much which neither Ferrier nor any of his co-laborers have learnt in the course of their researches. But we cannot be too careful in the present state of our knowledge in guarding against supposing an analogy, or sameness rather, between man and animals in regard to the functions, which, as already said, Ferrier supposes to be the antero-frontal and the occipital regions of the brain.