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with regard to the latter that there is most uncertainty. Schilferl says : "With regard to the angular gyrus the experiments with Sanger Brown were entirely contradictory to those of Ferrier and Yeo. In animals in which the grey matter of this convolution was destroyed on one or both sides we could discover no defect of vision." " He instances, too, the observations of Flechsig on the course of the fibres of the optic radiation. Tracing these during the process of myelination that observer found that none went to the angular gyrus and he therefore excludes this portion of the cortex from the visual area." Other observers, reasoning chiefly on clinical evidence, take an opposite view. Sir W. R. Gowers says: "The two half vision centres are probably blended in a higher visual centre in front of the occipital lobe. The arrangement is, however, complex. In each centre both fields are represented, but chiefly that of the opposite eye." " This region is also regarded as the mind vision-centre, and a lesion here is believed to cause therefore crossed amblyopia with some impairment of vision on the same side and mind-blindness. "In the very few post-mortem examinations in cases with crossed amblyopia the posterior and inferior part of the parietal lobe-i. e., the angular gyrus in its widest sense-has been involved in the disease. " As the

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