When Peter Kalm, the Swedish naturalist, was studying the natural history of New Jersey, he was much struck with the noises made by certain small frogs which he heard, and supposed that he saw; but it would appear, from a recent study of the subject by Prof. Garman, of Cambridge, Mass. that Kalm attributed the voices of one species to a very different and much larger frog. The reasons given for this opinion by Prof. Garman are conclusive; that author remarks; “Apparently the frog Kalm heard was not the one he caught. The cry is that of _Hyla Pickeringii_; the frog taken was probably ... the leopard, frog.” So far, Garman; but I am convinced my friend is mistaken, and that Kalm heard the shrill peeping of the little _Acris crepitans_, which is extraordinarily abundant, while, in the locality where Kalm was, Pickering’s _hyla_ is comparatively rare. I lingered long by the resounding marsh—so long that the chilly damp provoked an aguish pain, and admonished by it I turned toward the leafless trees upon the bluff, where I hoped to find a drier atmosphere. The moon was well upon her westward course when I reached higher ground, and what a change from the open meadows to gloomy woodland! The dark shadows of noonday are not repeated during a moonlit night. They are not only less distinct, but quivering, as though they, too, shivered as the air grew cold. It is not strange that one peoples the distance then with uncouth shapes, and sees a monster wherever moves a mite. However one may argue to himself that this is the same wood-path down which he daily passes without a thought, and that since sunset no strange creatures can have come upon the scene, he sees a dozen such, it may be, in spite of every effort to laugh them out of existence. Let a spider crawl over your face at noon, and you brush the creature from you almost unconsciously. Let a filmy cobweb rest upon your damp forehead at midnight, and you struggle to be rid of it, as though bound with a rope. The mingled sounds of myriad frogs, the hooting of owls, the rustling leaves beneath the shrew’s light tread, even the chirping of a dreaming bird, can not assure you. Every tree is the ambush of a lurking elf; ghosts and hobgoblins follow in your steps. I have abundant sympathy for those who, walking through moonlit woods, whistle to keep their courage up.