The tendency of small nebulae to gather in clusters has been known for some time. Stratonoff’s map of the distribution of faint nebulae in the Northern Hemisphere shows it very plainly. Max Wolf’s more detailed study of the ecliptic regions with the 16-inch Bruce camera and the 30-inch reflector demonstrates that within these larger regions of the sky where nebulae tend to congregate there are points of accumulation about which the clustering is more marked. He measured the positions of more than four thousand new nebulae, and devised a classification which, while admittedly formal, offers an excellent scheme for temporary filing until a significant system shall be constructed. The present paper has to do with certain clusters of small, faint nebulae which the writer found during the years 1914 to 1916 while photographing with the 24-inch reflector of the Yerkes Observatory. From about 1000 uncatalogued objects, 512 in 7 well-defined clusters were chosen for measurement. Known nebulae in the clusters numbered 76; hence there were, in all, some 588 objects, or an average of 84 per cluster. The fields are as given in Table I. The problem of measuring and reducing accurate positions of objects at a considerable distance from the center of plates taken with a reflector of so large a focal ratio, 1:4, presented serious difficulties. The area covered by each plate is a square of some 110´ to the side. With the full aperture the stellar images are sensibly round only within 5′ of the optical center of the plate. From there outward the coma becomes more and more prominent, distorting the images first into an oval, and finally, near the edge of the plate, into the shape of an arrow, while the point about which the images build up becomes more and more eccentric. For images of various sizes this point will be at various distances from the centers of figure, and at 40′ from the center will fall very nearly at the point of the arrow. This introduces at once an overwhelming magnitude-error, masking whatever distortion of the field may exist. TABLE I