Page:Microscopicial researchers - Theodor Schwann - English Translation - 1947.pdf/139

Rh are represented in pl. III, fig. 6, a, being spindle-shaped or longish corpuscles, which are thickest in the middle and gradually elongated at both extremities into minute fibres. They may therefore be described as consisting of a thicker portion, or body, and fibres, which proceed from it.

The body is either round or slightly compressed upon the sides. The surface is covered with very minute granules. Within the thickest portion of it lies ‘another small corpuscle of a circular or generally oval form, and which again encloses one or two small dark points, and accords entirely with the common cell-nucleus. It is therefore probable, that the entire corpuscle is a cell containing a nucleus. The nuclei have not a similar size in all the cells; there is a much more striking variation, however, in the relative size of the cells and the nuclei. In the largest cells, such as a, fig. 6, the body is almost as thick again as the nucleus, and it may be observed that the nucleus does not lie in the centre, but upon the wall of the cell. In most instances, however, the cells are relatively smaller, scarcely larger indeed than the nucleus; insomuch, that the fibres often appear to proceed immediately from the nucleus, as at 4 in the figure: the cell in that instance encompasses the nucleus quite closely. Cells frequently become separated during the process of preparation for the microscope, and float about singly in the water, with a portion of the fibres issuing from them. By causing them to roll, when so detached, it may be satisfactorily seen that many of them are somewhat flattened laterally, and that the nucleus is attached to the inside of the cell-wall. The larger cells, under such circumstances, appear as though the granulous aspect were produced by the external wall only, therefore by the cell-membrane, the interior being filled with a clear fluid.

The cells pass by a gradual process of acumination into the fibres, it being quite impossible to discern any defined boundary between them. The fibres are pale, minutely granulous like the cells, and frequently give off branches. Their course is usually straight. It is difficult to find out how they terminate; but they are generally lost in a bundle of extremely minute fibres.

The above-described corpuscles, then, are the fibre-cells of areolar tissue in the middle stage of their development, a con-