Structure of nerve fibres and synapses in some invertebrates

Although our knowledge of biological structure has long ceased to be limited to analysis into parts which can be seen directly with the eyes, and has been extended to the study of molecular structure, yet there are still large divisions of physiology whose development is being retarded by lack of histological data in the old sense, data about the visible structure of tissues. In the present state of nerve physiology there are a great many subjects about which such istological information is urgently needed. For instance, we are still far from agreement even as to the visible structure of axons, and the histologist may have an im-portant contribution to make to the search for surfaces, on the outside of, or within, the neuron