This latest publication of Professor Meynert’s was mentioned in the last number of _The Monist_ by Mr. Christian Ufer, in the department “Literary Correspondence.” Since its appearance Professor Meynert has died. His name has stood foremost for a great number of years in the ranks of psychiatrical investigators, and his contributions to the science to which he was devoted, have, perhaps more than those of any other, tended to its permanent advancement. The activity of his life has extended over a great number of years, and his labors have not only been applied to the theoretical interests of his science alone, but have also been directed—and this is the most important part of every scientist’s work—to bringing the results of his investigations into connection with the great body of knowledge at large, and especially to putting in popular form, and bringing within the reach of the general reader, the facts of the science which he contributed so much to establish. The present lectures date from the year 1868. They owe their origin to the identification in later years of the interests of medicine with the interests which every human being has at heart, of resolving the mysteries of mental operations generally. Their main subject is the description and investigation of the structure of the cerebral organs; and the elucidation in the light of such description of the psychical operations of the brain. The fundamental facts of this province are not difficult. The main thing required is to free ourselves from the impediments which artificial thought on this subject has at all times imported into the consideration of intellectual facts. Our knowledge in this domain is founded on observation and introspection; not upon dialectics. Phenomena, simply, are presented to observation, and not the ultimate essences of forces. So, too, the apparatus of observation and introspection give only their own phenomena. Their contents are the animated external world as it affects conscious beings, and involves, besides intuition, the facts of memory. Unpersonal inherited memories, which take the form of instinct, are not forthcoming. The present lectures do not pretend to give instruction in the anatomy of the brain _per se_, but simply in so far as it is necessary to the understanding of the brain’s mechanism. All things viewed, all things intuited are contents of consciousness, which in its limitations to the sense-impressions of the individual being, we term the ego, or _I_. In so far as the external world is the intuited contents of consciousness, the extent of the latter is increased, the ego, the _I_, expands into the secondary ego, or _I_. In this doctrine of a secondary ego the problems which grow out of the behavior of individuals towards the external world are resolved in the single explanation that the ego of each particular group of things seeks to preserve itself by internal and external motions. The ego is simply in the possession of itself