E. P., Delaware County, Pa.- " I enclose leaves of a species of Popidus which is planted in Philadelphia a good deal, to ask if thee would name it for me through the columns, of the Gardener's Monthly. I have none of the aments, but they (the staminate) are very similar to those of P. alba, appearing a couple of days before them, stamens about twelve, scales lacerate-fringed. The leaf-buds are not viscid, and the leaves, later in the season, become smooth on both sides. The bark is similar to that of P. alba, but rather more yellowish than that. I have puzzled over this a good deal,and concluded that it must be a variety of P. alba; but at the Centennial the other day, in the Swedish school-house, I saw dried specimens of P. tremula which resemble this considerably; but I think young leaves were present with the catkins, which is not the case with this."

[Popidus canecens. It is not uncommon as a street tree in Philadelphia, but is a worse suck-erer than P. alba. - Ed. G. M]