“In the first place,” he writes, “their numbers must be strictly limited, according to the nature of the subject illustrated and the space available. None must be placed too high or too low for ready examination. There must be no crowding of specimens one behind another, every one being perfectly and distinctly seen, and with a clear space around it.... Every specimen exhibited should be good of its kind, and all available skill and care should be spent upon its preservation and rendering it capable of teaching the lesson it is intended to convey.... Every specimen exhibited should have its definite purpose, and no absolute duplicate should on any account be permitted.” The purport of these golden words, which at the time they were written indicated an entirely new departure in museum arrangement and display, was, so far as possible, followed in the rearrangement of the mammal galleries. In the first place, the upper portions of the cases, which were far too high above the ground to permit of the proper exhibition of small specimens, were, except in those containing large mammals, closed up and employed for displaying the labels relating to the larger groups and the maps illustrating their geographical distribution. Then, again, the shelves, in place of being arranged one above another like those in a wardrobe, were reduced in number, and in most instances in width, so as to be suited to the best possible display of the specimens they were intended to carry. Duplicate specimens of all kinds, as well as representatives of species having but little general interest, were relentlessly weeded out and consigned to the store series; while efforts were made to procure new examples, mounted in the best possible manner, of all species—and these were by far the great majority—represented by badly-mounted, or old and faded specimens. This part of the business was found, however, to be a matter which must necessarily occupy much time, as it is impossible to procure examples of rare or large species, in a condition fit for stuffing, at the precise moment when they are required; and there is also the question of expense, which becomes very heavy indeed when renovating and replacing a collection of the proportions of that of the National Museum. This portion of the work has therefore been going on uninterruptedly ever since the first start was made, and is indeed being continued at the present time; for it has been found by experience that a collection of this nature, owing to the terribly bleaching effects of sunlight, requires constant renovation, and that exhibited museum specimens have only a definite and limited period, varying to a considerable extent according to the colour and nature of the hair in individual species, during which they are fitted to be publicly shown. Instead of a museum, when once arranged, being “a joy for ever,” it requires constant attention and renovation, so that even,