Let us now see what evidence of nerve-endings we find in or on the alveoli of the gland, examining one, or more accurately, a part of one (the round eminence). We shall see what fig. 1 presents. We see there two sets of nuclei; one kind oval, longish, stained lighter than the rest, of a pink hue (fig. 1, _m_), and these a further examination will demonstrate to be the nuclei belonging to the membrana propria, which have also been described before. Besides these nuclei, fewer in number, there is another kind, making up the bulk of the nuclei, more rounded in form (fig. 1, _g_), and of a deep-red color, which, in their turn, will prove to be the nuclei of the gland-cells; and these two are the only elements or structures that I have been able to demonstrate in a glandular alveolus. At one time I thought I had found in or on the alveoli the evidence of a network of fine nerves. Quite frequently one can observe longish, even spindle-shaped, often deeply stained, nuclei, which resemble very much those belonging to the fine nerve fibres. (Fig. 2, _n_, such nuclei are figured.) But so far, whenever I examined such a spindle-shaped nucleus more carefully, I found that it proved to be one of the nuclei belonging to the membrana propria, already described, and the form, as well as its dark color, was due to the fact that it had been examined edgewise. If, by manipulation, such a nucleus was turned over and compressed to present a flat surface, it would have an oval outline and be of a light-red color. Fig. 3 (_a_, _b_, _c_), shows the same nucleus as it appeared when seen edgewise, when seen from the flat and when seen in a position midway between these. Thus is also to be explained the demilune: If the section would strike a nucleus so that it would be seen only edgewise—especially if the membrana propria has a chance to roll up slightly—we should then have a deeply stained body, somewhat half-moon-shaped, the demilunes of the books. So far, nothing but the nuclei have been mentioned, and the observation might very appropriately be made, that there might exist some exceedingly fine and delicate nerve fibrils without nuclei. Such a system of structures would, of course, be almost impossible to demonstrate with any degree of certainty. I have not, of course, sufficient reason to deny such an arrangement, and would not consider it improbable if we had not, in the capillaries of the frog’s muscle (and other structures) evidence certainly not in favor of such an assumption. The fine nerve fibrils supplying the capillaries are richly supplied with nuclei, although the cells which build up the walls of the capillary are by far more insignificant elements than the secreting cells of the gland. Certain it is that as yet there is no evidence of the existence of such fine non-nucleated fibrils, arranged either in the form of a network or a bundle of fine branches.