is formed, as it were, by folding the entire brain in the form of an arch, the concave surface closing together over the fissure. The spinal marrow folds back upon itself and thus forms the cerebrum, leaving the Sylvian fissure to show the fold. This fissure is parallel to a line drawn from the end of the nose to the external opening of the ear, and about two inches above it, its middle point being over the ear. Below this fissure, and parallel to it, extend the three convolutions of the temporo-sphenoidal lobe, separated by two minor fissures (the larger one named the parallel temporal fissure"). § 63. The second great fissure is likewise named from the anatomist who first described it (Rolando, of Turin, in 1830). It arises near the middle and a half inch above the Sylvian fissure, and extends upward and backward about four inches to the median line separating the two hemispheres. It divides the frontal lobe from the parietal. It runs for its entire length between two convolutions, the ascending frontal and ascending parietal, very important because in them have been made the recent discoveries of localized functions. Three parallel convolutions (upper, middle, and lower) spring from the ascending frontal and extend to the median line of the forehead. Behind the ascending parietal convolution, and sepa rated from it by a long and deep fissure (the intraparietal, third in size and importance), is the supramarginal convolution, and below this the angular convolution, also important because it is the centre for the movements of the eyes. There is a fissure (the parieto-occipital) that separates the parietal from the occipital lobe, which also has three convolutions (upper, middle, and lower). § 64. This is an outline map of the convolutions. Now look at the results of recent investigations. The anatomists who examined the claims of phrenologists fifty years ago found only negative results. Longet, Magendie, Flourens, Matteucci, Schiff, and others declared that their experiments showed no evidence of such localization. Longet tried mechanical irritation, cauterization, and even galvanic currents on the brains of dogs, rabbits, and kids, without obtaining any sign of muscular contraction. But, in 1861, Broca, of Paris, gave a report of two cases of aphasia, and announced that loss of speech is caused by the disease of the back portion of the lower frontal convolution on the left side of the head (a point three inches above and forward of the orifice of the ear). *The subjoined is a roughly constructed cut of the brain, showing the main features. 1, 1, 1, Inferior frontal (below the inferior frontal fissure). 4, 4, 4, Ascending frontal (front of the fissure of Rolando). 5, 5, 5, Ascending parietal (between the Rolando and intraparietal fissures). 6, 6, Angular (above the parallel fissure.) 7,7, Superior temporo-sphenoidal (between the Sylvian and parallel fissures). 8, 8, 8, Middle temporo-sphenoidal (below parallel fissure). 9, 9, Inferior temporo-sphenoidal. 10, Superior occipital (behind the parieto-occipital fissure). 11, Middle occipital. 12, Inferior occipital. A, Supra-marginal (under the parietal eminence). B, Postero-parietal. Eckhard, six years later, discovered that convulsive movements in the extremities may be caused by removing portions of the cortical substance, or gray matter of the brain. (The cortical substance, or gray matter of the brain, is about one tenth of an inch in thickness, and covers the whole brain like a cortex or bark.) Meynert before this had arrived at the conclusion that the front part of the brain is used for functions of movement, while the back part is used for sensation. § 65. During the Franco-Prussian War, in 1870, Dr. Hitzig applied a galvanic current to a portion of the exposed brain of a wounded soldier, and noticed that it caused a contraction of the eyelids. After the war he and Dr. Fritsch made systematic experiments on lower animals with a continuous current, and were able to locate five centres of movement in the convolutions near the fissure of Rolando. Besides the centre for the movement of the tongue, already mentioned as discovered by Broca, they located the centre for the movements of the eyelids and upper part of the face just above the former; the centre for the muscles of the neck is situated in the back part of the upper frontal convolution; the centre for the movement of the arms (or fore legs) in the upper end of the ascending frontal; the centre for the movement of the hind legs just opposite of the former, across the fissure of Rolando, in the upper part of the ascending parietal convolution; the centre for the movement of the eyeballs in the angular convolution, just below and back of the marginal protuberances at the side of the head. The publication of these discoveries made an epoch in the study of the brain. Dr. David Ferrier, of London, used a faradic current instead of the continuous current, and succeeded eventually in locating fifteen centres of movement in the brain of the monkey. These centres, if stimulated, produce the following movements (the numbers and letters referring to Ferrier's map): (1) Advance the legs, as in walking; (2) complex movements of leg, foot, and trunk; (3) movements of tail; (4) movements forward and backward of fore limbs; (5) extension of arm and hand to reach something; a, b, c, d-movements of fingers and wrists and clinching of fist; (6) forearm raised to the mouth; (7) angle of mouth drawn back and elevated; (8) nose and upper lip elevated and lower lip depressed so as to expose the canine teeth; (9) mouth opened and tongue protruded; (10) mouth opened and tongue drawn back; (11) angle of mouth drawn back; (12) eyes opened widely, head and eyes turned to one side; (13 and 13*) rolling of eyeballs to one side; (14) drawing back of ears; (15) twisting of lip and nostril on one side. It will be readily seen that these are chiefly further specifications of the areas discovered by Hitzig and Fritsch: for movements of the hind legs (marked on maps of the brain E, in the upper portion of the ascending parietal convolution) we have No. 1 of Ferrier located in the same region.-Hitzig's fore-limb movements (marked D on maps of the brain, located in the upper portion of the ascending frontal) correspond to Nos. 4, 5, 6, a, b, c, d, of Ferrier, of which 5 and 6 occupy an area a little below D, and the others cover the middle and lower portions of the ascending parietal. The tail movement (No. 3) is between Nos. 4 and 5. Hitzig's neck and head movement (marked C, in back part of upper frontal) corresponds to No. 12 of Ferrier in locality. His face movements (marked B, in back part of middle frontal) correspond to Ferrier's Nos. 7, 8, 9, 10, and 11, all relating to the mouth in some way. Nos. 6 (which carries |