There is one point that is brought out in the table on page 14 that merits attention from the broad standpoint of economy. In all shells there is a proportion of unavoidable waste, since the entire weight of the shell can not be transformed into buttons. In very small shells we may expect an undue waste, on account of the fact that only one or two blanks can be cut out, leaving a larger bulk of shell in proportion to the number of blanks gained. On the other hand, in very large shells a high degree of waste is involved because of excessive thickness, which must be ground from the blanks, and because of the extra weight of the discarded portion. Somewhere between these extremes is the size of shell that yields the largest number of blanks as compared with the waste or the weight of shell that does not go into buttons. As shown by the data in the fifth column of the table, the shells a little above 2 inches in size are those (for this species) that make the best yield per ton for the small lines for which there is the greatest general demand. REASONS FOR THE PROPOSED 2-INCH LIMIT. Argument might be made in favor of a higher size limit as being still more favorable to the preservation of the mussels, but it is sufficient to say that the economic conditions would not justify a higher limit. At 2 inches a sufficiently severe restriction is placed upon the fishery, and to go further would be practically to prohibit the pursuit of shelling in so many localities that excessive hardship would be caused. As consideration thus far has been given almost exclusively to the niggerhead shell, the question may well be raised, Will the same limit apply to other species of shells? The minimum size of 2 inches suggested can be taken as an absolute minimum, since there is no species of any importance for which it would be too high. This minimum would not, however, give the same degree of protection to the larger forms, such as the washboard, the bluepoint, and the mucket. Should a minimum size be fixed with particular reference to any one of these varieties, it would necessarily be a good deal higher. In the present paper recommendation is made for this one-size limit alone, for the following reasons: 1. All conditions considered, it is the most appropriate limit that could be designated for the niggerhead mussel, which is at present the most important species of wide distribution, and which is, furthermore, the species most liable to rapid extermination. This and species closely like it, as the pigtoe, the pimple-back, and the maple-leaf, are chiefly those that are now being taken in the very small sizes. 2. The same size applies equally well to the related species just mentioned, as well as to the "hickory-nut," or "Missouri niggerhead," and the "butterfly."