Seventeen species. Hardy annuals, and green-house evergreen shrubs. Seed or cuttings. Common soil.

The following are good directions for the culture of the Heliotrope: -

"Prepare in August as many shallow thirty-two sized pots as will be required, by tilling them to the depth of an inch and a half with broken crocks, upon which a layer of the rough sittings of leaf mould should be laid; the remaining space should be filled with a mixture of finely sifted leaf mould and silver sand, previously well incorporated, which when pressed down firmly, should be exactly level with the border of the pots.

"For cuttings, the tips of the young shoots about three inches in length, should be chosen, and these should be taken off immediately below a joint or the base of a leaf bud.

"After removing two or three of the lower leaves, plant the cuttings in the pots prepared, about an inch and a half deep, and two inches apart; water them well with a fine rose two or three times, so that every part of the soil may be thoroughly moistened, which may easily be known by the water percolating through the bottom of the pots. If this is not attended to, and the surface soil alone is penetrated by the water, certain failure will be the result.

"The cuttings, when planted, should be removed to a cucumber or other frame, where a tolerably damp heat can be supplied; they should be kept shaded from the sun, and air admitted in small quantities, only during the hottest part of the day. In about a fortnight, the plants will begin to form roots, and the shading may be gradually diminished during the morning and afternoon; the quantity of air given them may be increased by degrees, and at the end of a month from the time ot planting, the cuttings will be ready for potting off singly.

" For this purposo large sized sixties.

If a press cannot easily be had, books may be employed. Next, some quires of unsized blotting paper must be provided. The specimens, when taken out of the tin box, must be carefully spread on a piece of pasteboard, covered with a single sheet of the paper, quite dry; then three or four sheets of the same paper must be placed above the plant, to imbibe the moisture as it is pressed out. It is then to be put into the press. As many plants as the press will hold may be piled up in this manner. At first, they ought to be pressed gently. After being pressed for about twenty-four hours, the plants ought to be examined, that any leaves or petals which have been folded may be spread out, and dry sheets of paper laid over them. They may now be replaced in the press, and a greater degree of pressure applied. The press ought to stand near a fire, or in the sunshine. After remaining two days in this situation, they should be again examined, and dry sheets of paper be laid over them. The pressure ought then to be considerably increased. After remaining three days longer in the press, the plants may be taken out, and such as are sufficiently dry may be put in a dry sheet of writing paper. Those plants which are succulent may require more pressure, and the blotting paper to be again renewed.

Plants which dry very quickly ought to be pressed with considerable force when first put into the press; and, if delicate, the blotting paper should be changed every day. When the stem is woody, it may be thinned with a knife, and, if the flower be thick or globular, as the thistle, one side of it may be cut away, as all that is necessary, in a specimen, is to preserve the character of the class, order, genus, and species. Plants may be dried in a box of sand in a more expeditious manner; and this method preserves the colour of some plants better. The specimens, after being pressed for ten or twelve hours, must be laid within a sheet of blotting paper. The box must contain an inch deep of fine dry sand on which the sheet is to be placed, and then covered with sand an inch thick; another sheet may then be deposited in the same manner, and so on, till the box be full. The box must be placed near a fire for two or three days. Then the sand must be carefully removed, and the plants examined. I not sufficiently dried, they may again be replaced in the same manner for a day or two. In drying plants with a hot smoothing iron, they must be placed within several sheets of blotting paper, and ironed till they become sufficiently dry.

This method answers best for dry -ing succulent and mucilaginous plants. When properly dried, the specimens should be placed in sheets of writing paper, and may be slightly fastened by making the top and bottom of the stalk pass through a slip of the paper, cut for the purpose. The name of the genus and species should be written down, the place where it was found, nature of the soil, and the season of the year. These specimens may be collected into genera, orders, and classes, and titled and preserved in a portfolio or cabinet. The method of preserving many of the cryptogamous plants is more difficult. on account of the greater quantity of moisture which they contain, and the greater delicacy of their texture." - En-cyc. Am.