Elements of psychology . nerve, which connectsan organ (muscle, gland, etc.) with a greater or smallermass of cells. The cells, on the other liand, are micro-scopic elements shaped like a flask or long-necked of the necks—for there may be more than one—seemsto be prolonged into the fiber, and is called the axis-cylin-der process of the cell. Both cells and nerves have nuclei,small dark points which are surrounded by nerves are also cut up at intervals by nodes resem-bling the divisions in a length of corn-stalk. See Figs. 1and 2. Some cells, however, are found without
Elements of psychology . nerve, which connectsan organ (muscle, gland, etc.) with a greater or smallermass of cells. The cells, on the other liand, are micro-scopic elements shaped like a flask or long-necked of the necks—for there may be more than one—seemsto be prolonged into the fiber, and is called the axis-cylin-der process of the cell. Both cells and nerves have nuclei,small dark points which are surrounded by nerves are also cut up at intervals by nodes resem-bling the divisions in a length of corn-stalk. See Figs. 1and 2. Some cells, however, are found without such connections, as far as microscopic analysis is able to go. And in many cases no direct continuity of structure has been discovered * Handbook, vol. ii. chap. i. 19 20 THE NERVOUS SYSTEM. between cells and fibers which are supposed to unite in acommon function. In these cases the fiber divides intonumerous ramifications, presenting the appearance of a treewith its top branches turned toward the cell. See Fig. Fig. 1.—From apiece of spinal cord. ^ and 5, ganglion-cells ; at Z>, axis-cylinder;p, protflplasmic process ; C, neuroglia-cells. (After Ranvier, from Edinger,Am. Ed.) The cells are largely gathered in masses or centers,toward which fibers from different regions or organs con-verge and ajjparently lose themselves. What is usuall}^called the brain is a series of such centers, varying in sizeand complexity from the cerebral cortex or rind, down-ward into the spinal cord. In the centers the cells are NERVE ELEMENTS. 21 separated by a substance called neuroglia(see Fig. 1), wliich may be simply a formof connective tissue not itself nervous—the opinion of the majority of neurologists—or a third nervous element whose func-tion is bound up svith that of the cells—aview supported by some later research. Combination of Nerve-elements in aSystem. The elements spoken of some-what artificially as cells and fibers have nofunctional existence apart from each othe
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