Gratifying as it is always to botanists to have any publication prepared by Prof. Asa Gray, the reception of "Supplements and Indexes" to the two parts already issued will not be without some regret. The great hope of Dr. Gray's life must have been to leave behind him a complete account of the flora of a country he has done so much to develop. Years ago, in connection with Dr. Torrey, a "Flora of North America" was begun, but the immense number of new species that came pressing in with the exploration of the territories led to an abandonment of the work before the compositae had been barely completed. This only took in for the most part the Polypetalous plants. Mr. Sereno Watson undertook an Index of this class, with references to where they were described, and this was the next best thing to bringing our knowledge down to date. Dr. Gray then worked on the compositae, and these were brought down to recent date. Finally the Gamo-petela, or Monopetela as they would once have been called, was undertaken, and these two parts bring the flora of North America down to date, leaving the diclinous class - a very large class - as well as the monocolyledous, to be provided for.

If new plants or new treatment of old ones did not interfere, Dr. Gray, though in his seventieth year, might reasonably have hoped to finish the work, but so much new appears that he can do little more than keep near perfect the work he has done. To accomplish this, the present supplement is issued. It adds 11 pages to Vol. 2, Part II, that has recently been issued, and 70 pages to Vol. 2, Part I. Complete indexes with the plants named in the supplement have been prepared.

Those who have already the two parts can buy this supplement separately for $1. Those who have not, can now buy the two first volumes with all the new gamopelatous plants complete to date. Even should Dr. Gray not be spared to complete the whole work of the North American flora, it will be a satisfaction to him to have done so well so large a part of it. The two parts bound in one may be had of the Curator of the Herbarium at Cambridge for $5.