During the present month there are four Public Exhibitions of Paintings in the city: that of the NATIONAL ACADEMY, of the ART-UNION, of the ARTIST'S ASSOCIATION, and the DÜSSELDORF GALLERY. The first three are composed mainly of the works of native American artists, and it is impossible to repress an expression of regret that some arrangement of union has not yet been effected, by which, at least, the works of the same men should not be exhibited gratis at one place, and for a charge at another. In the present state of things, the gallery of the Art-Union and that of the National Academy are brought into direct opposition, and this, beyond doubt, without the slightest jealousy on either side, as the works painted for the Academy and purchased by the Art-Union clearly show. But certainly the fact is lamentable enough to challenge immediate attention, and to induce a radical change. A free gallery of the selected works of artists will be very apt to carry the day against an exhibition at a quarter of a dollar of the miscellaneous and unselected works of the same men. But here we do not mean to vex this question farther. We aim at a general review of the peculiarities and excellences of each exhibition. It is undoubtedly in landscape art that American talent is destined first to excel, and the Academy exhibition and that of the Art-Union are added proofs of the fact. The landscapes are much the most distinguishing and distinguished feature. Mr. DURAND contributes several characteristic works. His style is so uniform and pronounced that it is never difficult to recognize his pictures. We should hardly say that he does better this year than usual, but we should certainly not say that he does worse. In the front rank of this department stand also KENSETT and CROPSEY, both of whom show beautiful results of summer study and winter work. Mr. Cropsey is mainly distinguished by a really gorgeous imagination. Proof of this is to be sought in the sketches of his portfolio rather than in his finished pictures, for in these a thousand influences seduce an artist away from the simplicity and splendor of his study into a care of public approbation and satisfaction. Mr. Cropsey is as yet too much enamored of the details and even of the mechanism of his art. And this is a tendency that is fatal to breadth and largeness of impression. Yet his "Southern Italy," and a "View in Rockland County," in the exhibition, are great advances in this respect. On the other hand, the two large American landscapes at the Art-Union, while the background in one is a splendid success, and the brilliant atmosphere of the other is no less successful, yet they are too much detailed, and the interest is nowhere sufficiently concentrated. Mr. Kensett is remarkable for his just sentiment and profound appreciation of natural beauty. It is a sentiment singularly free from sentimentality, and an appreciation as poetic as it is profound. The very delicacy of his touch and style