In the present transitional state of opinion concerning the mode in which the phenomena are produced that are popularly known under the name of "reflex paralysis," I cannot pass without notice the doctrines of these two observers. The reader will have perceived that, as regards the secondary paralytic symptoms observed in neuralgias, I explain the phenomena mainly on the theory of a process which is central, and not peripheral, in origin. And, even where, as in some few instances, it seems possible that the starting-point was an organic affection of some viscus, we must always consider the possibility that the link between this and the neuralgia and paralyses was a neuritis migrans travelling inward to the sensory centre, and from that passing over to motor centres and thus producing paralysis; or that, without the intervention of any truly inflammatory process, the continual impressions streaming in upon the cord from the original seat of organic disease may damage the nutrition of the sensory nerve-root, producing a partial atrophy, and that this process may extend to the motor root. It remains, however, to inquire whether the influence of powerful peripheral agencies may not, in a purely "functional" manner, disable the nerve-centres for a time, causing paralysis with or without neuralgia. The main supporters of such a doctrine are Dr. Handfield Jones[46] and M. Jaccoud.[47] Dr. Handfield Jones expressly rejects the theory of Brown-Sequard, as to spasm of the vessels in the nerve-centres, and we need not repeat his arguments on that head, because it seems to be generally felt that the vascular spasm theory will not account for the facts. Jones believes that the state produced in the nerve-centre by the peripheral influence is one of paresis from shock-depression, and that from the sensory centre this state can communicate itself to motor and vaso-motor centres, though commissural fibres. He does not believe in the existence of a special inhibitory portion of the nervous system: he believes that an impression may prove stimulating when it is mild, or paralyzing when it is strong; and that any afferent nerve may convey either the one influence or the other to the centres and thus produce secondary stimulus or secondary paralyses in various efferent nerves. Jones has the distinguished merit of being one of the first authors distinctly to perceive that pain must rank on the same level with paralysis: hence he sees nothing unintelligible in the communication of paralysis to a motor centre from a sensory centre that was in the state which the mind interprets as pain.