Fig. 2. Brain of a micro-cephalic idiot, which weighed only eight ounces although its possessor was an adult woman. The striking lack of development of the hemispheres is shown in their small size, whereby the cerebellum is almost entirely uncovered; moreover the convolutional pattern is simpler than that of an anthropoid ape’s brain.

Fig. 3. Left hemisphere, case of abscess of the frontal lobe: the convolutions and sulci are obliterated and the membranes thickened, so that the lore part of the brain presents the appearance of a membranous bag; this contained a large amount of pus.

Fig. 4. Right hemisphere seen from above instead of laterally: a hole corresponding to the middle of the central convolutions is seen, out which a tumour is displaced towards the middle line.

Fig. 5. Left hemisphere of a woman who for 11 years suffered with Motor aphasia paralysis of the lower half of the right side of the face, deviation of the tongue to the right and some weakness in the right leg and arm.

Fig. 6. Brain fromacase of apoplexy: the tops of the hemispheres have been sliced off to show the hemorrhage (dark patch) in the right centrum ovale, which has ruptured the fibres proceeding from the motor area of the brain, situated between the basal ganglia.

Fig. 7. Left hemisphere: a case of advanced dementia, showing atrophy of the convolutions, with deep and wide sulci intervening.

Fig. 8. The brain of an adult congenital imbecile. There is a very simple convolutional pattern in comparison with the other brains, shown in the figures. The convolutions are small, the secondary gyri are deficient in numbers. The sylvian fissure turns obliquely upwards and there is an obvious deficiency in the superior and inferior parietal lobes.

Fig. 9. Right hemisphere of a woman who for many years was the subject of sensory aphasia. The left hemisphere showed a similar lesion to the right but rather more extensive.

Fig. 10. Left hemisphere and cerebellum of a case of porencephaly. A local atrophy of the convolutions, owing to a vascular lesion before birth, is seen in the parletal