Possibly it may be thought that there is some mistake here—that things cannot be quite like this. Personally I have no knowledge on the subject—never having been to America—but here is what Dr. George M. Gould says, writing in _Science_ for October or November, probably 1895, since the number is referred to as “recent” in _Nature_ for December 5th of that year. “As soon as the sun has set and twilight is advancing, the Katydids in the trees begin to ‘tune up.’ The first notes are scattered, awkward and without rhythm, but if no wind is blowing thousands soon join in, and from time to time, until daylight breaks, there is no intermission.... In order to make my description clearer, let us suppose a thousand Katydids, scattered through the trees, to utter their several notes all at once, and call them Company A. Another thousand—Company B—at once answers them, and this swing-swong is kept up, as I say, all night. Company A’s note is the emphatic or accented note, and is more definitely and accurately a precise musical note, whilst the note of Company B varies from one to five half-tones below, the most conspicuous note being five. In the old-fashioned musical terms I learned as a boy, Company A is, e.g., clearly and definitely _do_, while the note of Company B is either _la_, or more certainly _sol_. Not only is Company A’s note more unisonal and definite, but it is firmer, more accented, and it seems to me that more insects join in this note than in the second. Careful observation has convinced me that no insect of Company A or Company B ever joins in the other company’s note. The rhythm is usually perfect, unless there is a disturbance by a breeze. A sharp gust upsets the whole orchestra, and confusion results, but the measured beat is soon refound. In the instants of confusion one can detect the steady see-saw of certain ones, as it were, ‘leaders,’ or first violinists, who hold the time-measure, despite the wind, and who soon draw the lost notes of the others once more into the regular measure or beat. I do not mean to say that by diligent attention one may not at times detect individuals sawing out of tune, stray fellows that are indifferent or careless, but the vast majority, usually even without a single exception, if there is no wind or rain, thus swing along, hour after hour, in perfect time. I have counted the beats several times, and find the number is always identical: thirty-four double beats, or sixty-eight single ones, in sixty seconds. The effect of the rhythm upon the mind is not unlike that of the woodman’s cross-cut saw, handled by two steady, tireless pairs of hands, although the Katydids give a larger volume of sound, and the _timbre_ is harsher.” Such is the account, and upon it Dr. Gould asks two questions: “What function does the orchestration subserve?” and “Is there anything comparable to it among other animals?”