Appendages of the style much longer than the stigmatic portion, lance-subulate, hispid, much exsert, erect-spreading. This plant was brought from Nevada Territory by Mr. Herbert C. Dorr. MIRABILIS L. _M. Californica_ Gray, Var. _villosa_ Kellogg. Stem about a foot in height, somewhat ascending, flexuous, divaricately branching, nodose, internodes slightly curved; minutely villous throughout. Leaves rounded-cordate, obtuse, entire, three to five-nerved; the uppermost ovate-cordate, petioles short, (one-fourth to one-sixth the length of the lamina). Flowers pedicellate, in loose terminal dichotomous panicles, with a solitary flower in the axils; perigonium pink, pedicels recurved in fruit. This plant, from the interior—Devil’s Gate and Carson River—differs much from the plate of the coast plant of the Mexican Boundary Report. It is not at all “glabrous,” nor are the flowers “sub-sessile;” the pairs of leaves are remote, with a much more open and spreading aspect; the flowers are pentandrous and deciduous. Mr. Harris exhibited a section of a pile, from a wharf at Rincon Point, which fell a few days since, having been destroyed by the boring of the _Teredo_, (properly a _Xylotrya_.) The material of the pile is Oregon pine; it had been in the water less than six years, but is now completely perforated in all directions. The subject of the best means of protection for piles, against attacks of the _Teredo_, was discussed at some length by various members. Dr. Ayres stated that, as yet, no reliable preventive had been discovered, except that of sheathing the pile with metal. Several years ago the same subject came before the Academy, and Drs. Ayres and Trask were appointed a Committee to investigate the subject. All external applications which have been proposed fail in practice, from the wearing away of the surface by the waves, and they are but little better than the natural bark. It has not appeared that the saving in time was equal to the expense incurred by thus protecting the piles. At Boston, where there are two species destructive of timber, they find no preventive, short of sheathing the piles with copper. In the French works on this subject, it has been stated that the bark affords no protection; but, on the contrary, aids the young animals in introducing themselves into the wood. This has not been found to be the case in this bay, where the bark does, on the contrary, assist in preserving the timber. The fact was also stated, by one of the members, that the piles of the wharfs in the southern part of the city suffer much from attacks of the _Teredo_; while those of the northern portion are comparatively exempt. The fact was mentioned, that piles have been entirely destroyed here in six months from the time they were placed in the water.