[1] In 1872, while a Commissioner of Health, I had occasion to examine and report on the causes of the high death rate during the summer months in the city of New York. The chief cause was determined to be the excessive heat which characterizes those months. It was recommended in the report to the Board of Health that legislation be secured empowering and requiring the Department of Parks to plant and cultivate trees, shrubs, plants, and vines in all the streets, avenues, and public places in the city. A bill was drafted and introduced into the Legislature, but it did not become a law, and no further effort has been made to secure such legislation. Meantime, two tree-planting societies have been established, one in the Borough of Brooklyn and the other in the Borough of Manhattan, which are endeavoring to awaken public interest to the importance of planting a suitable number and variety of trees in the streets for purposes of ornamentation. The aim of this paper, which is largely based on the report of 1872, is to revive the project of giving the Department of Parks jurisdiction over the trees in the streets, and require it to plant and cultivate additional trees, shrubs, plants, and other forms of vegetation for the improvement of the public health and for the purpose of ornamentation. [2] Man and Nature. G.P. Marsh, New York, 1872. [3] It is interesting to notice, in this connection, the remark of Angus Smith, that a temperature of 54° F. is important in the decomposition of animal and vegetable matter. [4] Public Parks. By John H. Rauch, M.D., Chicago, 1869. [5] Les Arbres, quoted by Marsh. [6] The late Dr. Francis remarked that he had noticed a marked increase in the fatality of diseases in sections of the city after the removal of trees and all vegetation. MIVART'S GROUNDWORK OF SCIENCE.[7] BY PROF. WILLIAM KEITH BROOKS. If books like this by Professor Mivart, who holds that "the groundwork of science must be sought in the human mind," help to teach that the greatest service of science to mankind is not "practical," but intellectual, they are worthy the consideration of the thoughtful, even if this consideration should lead some of the thoughtful to distrust Mivart's groundwork, or to doubt whether it is firm enough for any superstructure. Many, no doubt, think the desire to know a sufficient groundwork for science, believing that they wish to know in order that they may rightly order their lives; but the school to which Mivart belongs tells them all this is mere vulgar ignorance, since the groundwork of science is, and must be, something known, rather than a humble wish to know.