Many years ago Torrey and his pupil, Asa Gray, commenced the Flora of the United States; but by the time the work had reached the Compositae or Aster-like plants, the boundaries of the United States had so expanded that for this and other reasons, the work had to stop. Torrey is now no more; but Dr. Gray still active, though advanced in life, has continued the preparations for a great work, and which is now, we believe, nearly completed. A part of it is now issued, and the rest will soon follow. This part starts from where the old work of Torrey and Gray left off, and is, therefore, the second part of volume first; an excellent idea under the circumstances, especially as Watson's Bibliography, noticed last month, gives all the references to what part first would cover.

It is to be hoped that Professor Gray will be spared yet many years to see the full completion of what will be a magnificent contribution to American Botany. It is advertised at six dollars, but we paid but five for our copy from Mr. John H. Redfield, of the Philadelphia Academy of Natural Sciences, who by purchasing a large quantity, has given his friends the benefit of what commission his work would be entitled to.