The union of philosophy and theology is the mark of the middle ages, but in Occam their severance is complete.
It has been maintained that this tendency to a severance of the hybrid stock into its components must favour the persistence of a new character of large volume suddenly appearing in a stock, and the observations of Mendel have been held to favour in this way the views of those who hold that the variations upon which natural selection has acted in the production of new species are not small variations but large and " discontinuous."
A little later the breaking down of the whole axon, both axis cylinder and myelin sheath alike, seems to occur simultaneously throughout its entire length distal to the place of severance.
Similarly, when the axons of the motor spinal cells are by severance of the nerve trunk of a muscle broken through, the muscle cells undergo "degeneration" - dwindle, become fatty, and alter almost beyond recognition.
These muscles exhibit a certain constant condition of slight contraction, which disappears on severance of the nerve that innervates the muscle.