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vous system. The objection may be raised that the period which elapsed was not long enough, that the degeneration was simply incomplete, that the distal endings of the fibers form the net. works and that these were still in their normal condition. But we have already seen that the distal endings of most of the medullated nerves, the terminal fibrillae in the sensory organs, have completely degenerated. Why do the fibers of the net. works alone fail to show similar changes?
It has been shown in the first part of this paper that the fibers of these networks are nerve fibers. It cannot be maintained therefore that they do not degenerate because they are non-nervous structures. The only explanation of their immunity from the degenerative changes which affect the isolated medullated nerves is that the cells of the network exert upon them a distinct trophic influence. The cells are then something more than sheath cells or connective tissue cells as BARDEEN and others have asserted. The medullated fibers of the palate are well supplied with sheath cells but this does not prevent their degeneration when separated from their ganglion cells. We can only conclude that the cells of these networks are true nerve cells in that the integrity of the fibers is dependent upon them. This is in strict agreement with the conditions which we find in the nervous system of the lower animals, and substantiates the conclusions of BETHE and LEONTOWITSCH
As to whether these networks of nerve cells and fibers will retain their integrity indefinitely when severed from all connection with the central nervous system, we do not know at present. Experiments are in progress to determine whether they also will degenerate in the course of a few months, or whether they possess the power of regenerating new fibers. BETHE (:03) maintains that the sheath nuclei are modified nerve cells and still retain their primitive function of neurogenesis. It might be expected that these peripheral nerve cells possess a similar function. Our present data are not sufficient however to warrant the assumption of LEONTOWITSCH that there is a constant process of physiological regeneration going on in the skin, and that the subepithelial network is transformed into the peripheral portion of a neurite from a sensory ganglion cell. It seems to me rather that in these networks of nerve cells and fibers we have to do with primitive nervous structures more or less independent of the central nervous system, structures which, as BETHE points out, correspond to the diffuse nervous system of many invertebrates, and which are connected, on the one hand with the integument, and on the other hand with the nonstriated musculature.
1. The palatine branch of the seventh cranial nerve forms a plexus of medullated fibers in the palate of the frog; from this plexus fibers pass, to end by branching in the sensory organs of the epithelium.
2. The innervation of the sensory organs of the palate is not as diagrammatic as has been asserted; a diffuse network of neurofibrillae connects different sensory neurones, and puts the sensory organs into communication. 3.
A network of cells and non-medullated fibers extends throughout the deeper layers of the palate and forms a close meshwork about the walls of the vessels.
Immediately beneath the epithelium is found another network of cells and fibers; sensory fibrils from it end in the epithelium, and it is also connected with the perivascular network.
5. The fibers of the networks are nervous structures for (a) they are not demonstrated by specific stains for elastic and connective tissue; (b) they are composed of neurofibrillae; (c) they are often directly continuous with medullated nerves.
6. Neurofibrillae are present in the cells of the networks, but most of them pass through without forming a basketwork about the nucleus.
7. When the nerves of the palate are isolated from their ganglion cells the medullated fibers which end in the epithelium degenerate at the expiration of 25 to 35 days; the myelin sheaths disintegrate, and the axis cylinders fail to stain.
Under the same conditions both the cells and fibers
of the subepithelial and perivascular networks stain in a normal manner and show no degenerative changes in their structure. 9.
Some of the cells of the network are therefore true nerve cells and exert a trophic influence upon the fibers connected with them.
The networks are comparable to the diffuse nervous system of certain invertebrates, and their existence is incompatible with the idea that the nervous system is composed of of distinct cellular units.
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THE BEGINNINGS OF SOCIAL REACTION IN MAN
AND LOWER ANIMALS.
By C. L. HERRICK,
Socorro, New Mexico.
It seems to be easy to employ the word "social" in a very slip-shod manner and it may very well be that greater care in its definition would remove several bones of contention that are being worried from time to time in the journals.
When we admit that human experience “polarizes” (to use Professor Baldwin's expression) into ego and alter extremes, it becomes necessary very carefully to guard what is meant by the social self or social consciousness. CLIFFORD, and other writers since, have written of a tribal conscience or tribal self. Such expressions may easily be interpreted as though society were possessed of a consciousness in the same sense that the individual is. Now this is, of course, nonsense, or rather, a frequently exposed fallacy.
When we speak of the social self we mean the social reflected in the individual or else we mean an abstraction of common elements in the individual selves constituting the society, which common factors we may thereafter use, like an algebraic expression, as though it had an independent existence. It would be of immense advantage in simplifying philosophical and anthropological inquiry if some sort of an agreement could be reached as to the use of words in this connection. Ought we not carefully to distinguish the two elements just referred to ? Let us, for example, call the first the "socius consciousness," meaning thereby all that portion of our conscious acts which involves the recognition of other-in-self and self-in-other, or if the line cannot be drawn, our conscious acts in so far as this implication is under consideration. Let the second element be