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Fig. 9. Tracy Planter.

It is a common statement that seeds can never revive if allowed to become thoroughly dry after they have begun to sprout. This is an error. Wheat, oats, buckwheat, maize, pea, onion, radish and other seeds have been experimented upon in this direction, and they are found to re-germinate readily, even if allowed to become thoroughly dry and brittle after sprouting is well progressed. They will even re-germinate several times. Wheat, peas and other seeds have been carried through so many as seven germinations after the radicle had grown a half inch or more and the seeds had been sufficiently dried in each trial to render them fit for grinding.

Damping-off is a common ailment of young seedlings and cuttings. The stem becomes brown and constricted at or near the surface of the soil, and it soon rots and falls over. The top of the plant often remains alive and fresh for several days after it has fallen. A fungus is supposed to cause damping-off. The conditions which seem to particularly favor the development of this fungus are a moist and close atmosphere, crowding and careless watering. Plants are particularly liable to damp-off if only sufficient water is applied to keep the surface moist while the under soil remains dry. Hot sand, sifted over the plants, will check it, but there is no complete remedy. Attention to the above suggestions will serve as a preventive.

The transportation of certain kinds of seeds over long distances, especially on sea voyages, is often beset with difficulties. Thick-meated or soft seeds may become too dry if stored in a warm place or too moist if stored in a cool one. The humid atmosphere of the ocean is fatal to some seeds unless they are well protected, and the moist and hot climates of some tropical countries destroy many seeds of cooler regions before they can be planted. Thin-coated seeds demand dryness and air, and bony seeds usually need moisture and a more confined atmosphere. Most seeds may be sent dry and loose in coarse paper packages under all ordinary circumstances; but if they are to traverse very hot and moist climates, they should be sealed in tin cases or very securely wrapped in oiled paper, in which case the seeds should be thoroughly dried before being packed. Small seeds which are liable to become moldy may be packed in finely powdered charcoal. Apple and pear seeds are often imported in this manner. The seeds or fruits of woody plants require more careful management. They should generally be transported in some sort of stratification. A favorite method is to place them in boxes or jars, mixed with naturally moist sand or sawdust, or slightly moist dead sphagnum moss. Some prefer to seal the packages hermetically, but under ordinary conditions this is unnecessary. In transit, the packages should be stored in a medium and uniform temperature. Even acorns, which are often difficult to transport over long voyages, may be carried in this manner with safety. It is important that the soil should not be wet. Natural soil from a dryish and loamy pasture is excellent. In some cases it is better to sprout the seeds in the native country and ship the seedlings in a closed or Wardian case.

It should be borne in mind that actual plantings rarely give so good results as seed tests, from the fact that conditions are more variable. There is often a variation of over fifty per cent. even when the planting has been carefully done. This is proof that liberal seeding should always be practiced.

Spores.—Ferns, lycopodiums and selaginellas are often grown from spores. The general conditions adapted to the germination of seeds are also suitable for the germination of spores, but extra care must be taken with the drainage. If a pot is used, it should be half or more filled with drainage material, and the soil should be rendered loose by the addition of bits of brick, charcoal, cinders or other porous materials. The surface soil should be fine and uniform. Some place a thin layer of brick dust upon the surface, in which the spores are sown. It is a frequent practice to bake the soil to destroy other spores which might cause troublesome growths. The spores should be sprinkled upon the surface and should not be covered. The pot should be set in a saucer of water and it should be covered by paper or a pane of glass if the sun strikes it. Better results are obtained if the pot or pan is placed inside a propagating-frame or under a bell-glass. In place of earth, a block or small cubes of firm peat or sandstone may be employed. The block is placed in a saucer of water and the spores are sown upon its surface. Water should not be applied directly to the spores, as it is apt to dislodge them.

The period of germination varies in different species, but three to six weeks may be considered the ordinary limits. While still very small, the plantlets should be pricked out, and for some time thereafter they should be subjected to the same conditions as before. Spores are so exceedingly small and light that the greatest care must be exercised in growing them. In order to gather them, the fronds may be cut as soon as the sori or fruit-dots turn brown, and stored in close boxes or paper bags.

Note.—For tables of weights and longevities of seeds and quantities required for given areas, consult Horticulturist’s Rule-Book.

CHAPTER II.

SEPARATION.

Separation.—The act or process of multiplying plants by means of naturally detached asexual organs, or the state or condition of being so multiplied.

Separation is effected by means of bulbs, bulbels, bulb-scales, bulblets, corms, tubers, offsets, crowns and sometimes by buds.

Bulbs of all kinds are specialized buds. They are made up of a short and rudimentary axis closely encased in transformed and thickened leaves or bulb-scales. These thickened parts are stored with nutriment which is used during subsequent growth. Bulbs occur only in plants which are accustomed to a long period of inactivity. Many bulbous plants are peculiar to dry and arid regions, where growth is impossible during long periods. A bulb is, therefore, a more or less permanent and compact leaf-bud, usually occupying the base of the stem underground and emitting roots from its lower portion. Bulbs are conveniently divided into two great classes—the scaly, or those composed of narrow and mostly loose scales, as in the lily, and laminate or tunicate, or those composed of more or less continuous and close-fitting layers or plates, as in the onion.

Fig. 10. Bulb of Lilium candidum.

Bulbs often break up or divide themselves into two or more nearly equal portions, as in Lilium candidum, shown one-third natural size in Fig. 10. The parts may be separated and treated as complete bulbs for purposes of propagation. This division or separation of bulbs proceeds in a different manner in nearly every species, yet it is so obvious that the novice need not be perplexed by it. Almost any breaking apart of these loose bulbs, if only a “heart” or central axis remains in each portion, is successful for purposes of slow multiplication; but when flowers are desired it is usually inadvisable.

Bulbous plants multiply most easily by means of bulbels—often also called bulbules and offsets—or small bulbs which are borne about a large or mother bulb. In some lilies, as Lilium candidum, the bulbels form at the top or crown of the mother bulb, and a circle of roots will be found between them and the bulb; in others, as L. speciosum and L. auratum, they form on the lower part of the flower stalk. In some species the bulbels are few and very large, or even single, and they bloom the following year. In such cases the bulb undergoes a progressive movement from year to year after the manner of root-stocks, the bulb of one year forming a more or less distinct one above and beyond it which continues the species, while the old one becomes weak or dies. This method of bulb formation is seen in the cut of Lilium pardalinum, Fig. 11. In the hyacinth the bulbels form at the base of the bulb.

Fig. 11. Bulb of Lilium pardalinum.

Bulbels vary greatly in size and frequency in different species. Sometimes they are no larger than a grain of wheat, and in other plants they are as large as hickory-nuts. In some species they are borne habitually underneath the scales of the mother bulb. These bulbels are often removed when the mother bulbs are taken up, and they are usually planted in essentially the same manner as the bulbs themselves, although it is desirable to place them, at least for the first year, in a bed or border by themselves. Or if they are especially small and delicate they may be planted in pots or flats and be treated about the same as single eye cuttings. In some lilies the bulbels are allowed to remain attached and the whole mass is planted in the fall in close drills. Sometimes the larger lily bulbels will produce flowers the following season, but they usually require the whole of the season in which to complete their growth. The second fall they are ready to be permanently planted. Bulbels of some plants require a longer time in which to mature into bulbs.

Fig. 12. Cut Hyacinth Bulb.

Fig. 13. Hollowed Hyacinth Bulb.

Bulbels are often produced by an injury to the bulb. Growth of stem and leaves is prevented or checked and the energy is directed to the formation of minute buds, or bulbs, in the same manner as adventitious buds form upon a wounded stem. Advantage is taken of this fact to multiply some bulbous plants, and in the case of the hyacinths, at least, the mutilation of bulbs for this purpose is practiced to a commercial extent. Hyacinth bulbs are cut in two, or are slashed in various ways. The favorite method is to make two or three deep transverse cuts into the base of the bulb. The strongest bulbs should be chosen and the operation is performed in spring or early summer when the bulb is taken up. The bulbs are sometimes hollowed out from the under side for half or more of their length. This operation is sometimes performed later in the season than the other, and precaution should be exercised that the bulbs do not become too moist, else they will rot. Hollowed bulbs should be well dried before being planted. Both methods of preparing hyacinth bulbs are shown in Figs. 12 and 13 which are adapted from Gardeners' Chronicle. Fig. 14 shows a portion of the base of a cross-cut bulb, with the adventitious bulbels. The mutilated bulbs are stored during summer, and are planted in fall or spring. The wounded bulbs produce very little foliage, but at the end of the first season the bulbels will have formed. The bulbels are then separated and planted by themselves in prepared beds. Several years are required for the bulbels to mature into flowering bulbs. Some of the strongest ones may produce flowering bulbs in three years, but some of them, especially those obtained from the hollowed bulbs, will not mature short of six years. This method of propagating hyacinths is confined almost entirely to Holland.

Fig. 14. Cross-Cut Bulb.

The scales of bulbs are often employed to multiply scarce varieties. From ten to thirty of the thicker scales may be removed from the outside of the bulb without serious injury to it. These are treated in the same manner as single eye cuttings. They are usually handled in flats or propagating-frames, and are pressed perpendicularly into a light and loose soil—half sharp sand and half leaf-mould—for nearly or quite their entire length, or are scattered in damp moss. Keep the soil simply moist, and for hardy and half-hardy species keep the temperature rather low—from 45° to 60°. Slight bottom heat may sometimes be given to advantage. In from three to ten weeks a little bulbel, or sometimes two or more, will appear at the base of the scale, as shown in Fig. 15.

Fig. 15. Bulb-Scale.

These pots or flats may be plunged out-doors during summer if the planting was done in winter, or the scales may be potted off or transferred to the open border as soon as rootlets have formed. It is the common practice with most hardy species to allow the scales to remain in the original flats during summer and to cover them the next fall, allowing them to remain out-doors over winter. The succeeding spring they are shifted into a bed or border, and by the next fall—having had two summers' growth—most species will be ready for permanent planting in the flower border.

A bulblet is a small bulb borne entirely above ground, usually in the axil of a leaf or in the inflorescence. Familiar examples occur in the tiger lily and in “top” onions. In the former instance the bulblets are direct transformations of buds, while in the onion they are transformed flowers. It is impossible to draw any line of separation between bulblets and buds. In some plants, certain buds detach themselves and fall to the ground to multiply the species. Sometimes these buds vegetate before they fall from the plants, as in the case of various ferns. For purposes of propagation, bulblets are treated in the same way as bulbels, and like them, they reproduce the variety upon which they grow. They will develop into full grown bulbs in from one to three years, according to the species.

Fig. 16. Gladiolus Corm.

A corm is a bulb-like organ which is solid throughout. Familiar examples occur in the gladiolus and crocus. Cormous plants are multiplied in essentially the same manner as bulbous species. As a rule, a new corm is produced each year above the old one, and this commonly bears flowers the following season. This renewal is well shown in the gladiolus, Fig. 16. The illustration shows a gladiolus bottom, half size, when taken up in November. At the base are seen the withered remains of the corm which was planted in the spring, and above it the new corm which will furnish bloom the following season. A number of cormels or “spawn” have also appeared. These may be planted out in a border or bed and will produce mature bulbs in one or two seasons. The larger ones, under good treatment, will often produce bulbs an inch in diameter the first season. Some growers keep the cormels a year and a half before planting them out, as they are thought to vegetate more evenly under such treatment; in this case they should be placed in sand to prevent too great drying out.

Adventitious cormels may be produced by various methods of wounding the mother corm, and this practice of exciting them is often necessary, as some varieties do not produce cormels freely. Each bud on the top or side of the corm may be made to produce a separate corm by cutting a deep ring around it, so as to partly divide it. Or the corm may be directly cut into as many separate pieces as there are buds or eyes, after the manner of cutting potatoes, but these pieces are usually handled in flats where temperature and moisture can be controlled. Almost any injury to such vigorous corms as those of the gladiolus and crocus will result in the production of cormels, if care is taken that the corms do not become so cold and wet that they will rot.

A tuber is a prominently thickened portion of a root or stem, and it is usually subterranean. The potato, sweet potato and dahlia furnish good examples. Tuberiferous plants are multiplied by planting these tubers whole, or the tubers may be cut into small portions as described in Chapter IV, in the descriptions of cuttings. In hardy species, the tubers may be allowed to remain in the ground during winter, but they are generally dug in the fall and stored in a dry and cold place, but where they will not freeze.

An offset is a crown or rosette of leaves, usually borne next the surface of the ground, which detaches itself and forms an independent plant. The best examples occur in the house-leeks, plants which are more familiarly known as “hen and chickens” and “man and wife.” These offsets take root readily, and in propagating there is no other care necessary than to remove and plant them.

A crown is a detachable portion of a root-stock bearing roots and a prominent bud. Rhizomes or root-stocks multiply individuals and extend the distribution of the species by means of a progressive movement of the crowns. The root-stock grows during summer, and at the end of the season each branch develops a strong terminal bud which usually produces a flowering stem the following season. The root-stock gradually dies away at its old extremity, and in a few years a single individual gives rise to a considerable patch. This is well shown by the common May-Apple or podophyllum.

Fig. 17. Lily of the Valley Crown.

In some species these crowns are removed in the autumn and are planted and handled in much the same manner as bulbs. The crown or pip of the lily of the valley, shown half size in Fig. 17, is obtained in this manner.

CHAPTER III.

LAYERAGE.

Layerage.—The operation or practice of making a layer, or the state or condition of being layered.

Layer.—A shoot or root, attached to the parent plant, partially or wholly covered with earth with the intention that it shall take root and then be severed from the parent.

Stolon.—A decumbent shoot which, without the aid of man, takes root and forms an independent plant.

Many plants habitually propagate by means of decumbent shoots and runners. These shoots become more or less covered with earth or leaves, and roots are emitted, usually at the joints. In many cases, the old shoots die away and an entirely independent plant arises from each mass of roots. In other plants, the shoots remain attached to the parent, at least for a number of years, so that the plant comprises a colony of essentially distinct individuals. Great numbers of plants which do not propagate naturally by means of layers are readily increased by this means under the direction of the grower. In most cases it is only necessary to lay down the branches, cover them with earth, and allow them to remain until roots are well formed, when they can be severed from the parent. Layering is one of the simplest methods of propagation, as the mother plants nurse the layer plants until they can sustain themselves. It is a ready means of multiplying hard-wooded plants which do not grow well from cuttings.

All vines, and all plants which have runners or long and slender shoots which fall to the ground, may be multiplied readily by layerage. Among fruits, the black-cap raspberry is a familiar example. The canes of the current year bend over late in summer and the tips strike the earth. If the tip is secured by a slight covering of earth, or if it finds lodgment in a mellow soil, roots are emitted and in the fall a strong bud or “crown” or “eye” is formed for next year’s growth. The parent cane is severed in the fall or spring, some four or six inches above the ground, and an independent plant, known as a “root-tip,” as shown in Fig. 18, is obtained. In this instance, as in most others, it is immaterial at what point the parent stem is severed, except that a short portion of it serves as a handle in carrying the plant, and also marks the position of the plant when it is set. The black raspberry propagates itself naturally by means of layers, and it is only necessary, in most cases, to bring the soil into a mellow condition when the tips begin to touch the ground in order that they may find anchorage. This layering by inserting the growing point has the advantage of producing very strong “crowns” or plants in autumn from shoots or canes of the same year, and it should be more generally practised. Even currants, gooseberries, and many other plants can be handled in this way.

Fig. 18. Raspberry tip.

Fig. 19. Covered Layer of Viburnum.

In most cases of layerage it is necessary to lay down the branches and to cover them. The covering may be continuous, as in Fig. 19, or it may be applied only to the joints or restricted portions of the shoot, as illustrated in Fig. 20. In either case, the covering should be shallow, not exceeding one to three inches. If the shoot is stiff a stone or sod may be placed upon it to hold it down; or a crotched stick may be thrust down over it, as in the “pegging down” of propagators.

Fig. 20. Layered Shoots.

The strongest plants are usually obtained by securing only one plant from a shoot, and for this purpose the earth should be applied only at one point, preferably over a bud somewhere near the middle of the shoot. If the buds are close together, all but the strongest one may be cut out. If more plants are desired, however, serpentine layering may be practiced, as shown at A in Fig. 20. The shoot is bent in an undulating fashion, and from every covered portion roots will form and a plant may be obtained. The covered layer also possesses the advantage of giving more than one plant, but the roots are apt to form so continuously that definite and strong plants are rarely obtained; these rooted portions may be treated as cuttings, however, with good results. The grape is sometimes propagated by serpentine layering.

Stiff and hard-wooded plants do not often “strike” or root readily, and in order to facilitate rooting the branch is wounded at the point where a new plant is desired. This wounding serves to induce formation of adventitious buds at that point, and to check the growth of the branch at the tip. It is a common practice to cut the branch about half in two obliquely, on the lower side. This operation is known as “tongueing.” "Ringing" or girdling, twisting, notching, and various other methods are employed, none of which, perhaps, possess any peculiar advantages in general practice. Some propagators cut all the buds from the covered portion. In this case the free and protruding end of the layer is expected to form the top of the new plant. “Arching,” or very abrupt bending, as in serpentine layering, serves the same purpose and is the only attention necessary in most vines.

When large numbers of plants are desired, as in commercial nurseries, it is often necessary to cut back the parent plant to the ground, or very nearly so, for the purpose of securing many shoots fit for layering. A plant which is cut back in the spring will produce shoots fit for layering the following spring; or some species will produce them in abundance the same year if layers of green or immature wood are desired. These parent or stock-plants are called “stools” by nurserymen.

Fig. 21. Mound Layering of Gooseberry.

In many species layerage is performed to best advantage by heaping earth over the stool and around the shoots. This is known as mound or stool layering. The shoots send out roots near the base and straight, stocky plants are obtained. The English gooseberries are almost exclusively propagated in this manner in this country. Fig. 21 shows a row of mound-layered gooseberries. The shoots are allowed to remain in layerage two years, in the case of English gooseberries, if the best plants are wanted, but in many species the operation is completed in a single season. Quinces and Paradise apple stocks are extensively mound-layered. The practice is most useful in those low plants which produce short and rather stiff shoots.

As a rule, the best season for making layers is in spring when the leaves are forming. Rooting progresses rapidly at that season. Many plants “bleed” if layered earlier in the season. Hardy shrubs may be layered in the fall, either early or late, and if an incision is made, a callus will have formed by spring. If rapid multiplication is desired, the soft and growing shoots may be layered during the summer. This operation is variously known as “summer,” "herbaceous," “green” and “soft” layering. Comparatively feeble plants usually result from this practice, and it is not in common favor.

Fig. 22. Pot layerage.

Pot layering, circumposition, air layering and Chinese layering are terms applied to the rooting of rigid stems by means of surrounding them, while in their natural position, by earth or moss, or similar material. The stem is wounded—commonly girdled—and a divided pot or box is placed about it and filled with earth (Fig. 22). The roots start from above the girdle, and when they have filled the pot the stem is severed, headed back, and planted. Pot layering is practiced almost exclusively in greenhouses, where it is possible to keep the earth uniformly moist. But even there it is advisable to wrap the pot in moss to check evaporation from the soil. Some plants can be readily rooted by wrapping them with moss alone. Pot layering is employed not only for the purpose of multiplying plants, but in order to lower the heads of “leggy” or scraggly specimens. The pot is inserted at the required point upon the main stem, and after roots have formed abundantly the top may be cut off and potted independently, the old stump being discarded.

Fig. 23. Layering pot.	Fig. 24. Layering cone.
Fig. 25. Layering cup.	Fig. 26. Layering cup.

Fig. 27. Compound layering pot.

The French have various handy devices for facilitating pot layering. Fig. 23 shows a layering pot, provided with a niche in the side to receive the stem, and a flange behind for securing if to a support. Fig. 24 represents a layering cone. It is made of zinc or other metal, usually four or five inches high, and is composed of two semi-circular wings which are hinged on the back and are secured in front, when the instrument is closed, by means of a hinge-pin. A cord is inserted in one side with which to hang it on a support. A cup or pot with a removable side is also used. This is shown open in Fig. 25 and closed in Fig. 26. An ingenious compound layering pot is shown in Fig. 27. The main stem or trunk of the plant is carried through the large opening, and the branches are taken through the smaller pots at the side. Kier’s layering boxes or racks are shown in Figs. 28 and 29. The trays are filled with earth and the branches are laid in through the chinks in the border and are treated in the same manner as ordinary out-door layers. These racks supply a neat and convenient means of increasing greenhouse plants which do not readily strike from cuttings.

It is well to bear in mind that when layers do not give strong plants, they can be divided into portions and treated as ordinary cuttings. This is an important operation in the case of rare varieties which are multiplied by means of soft or green layers, as some of the large-flowered clematises and grapes. The weak small plants are handled in a cool greenhouse or under frames, usually in pots, and they soon make strong individuals.

Fig. 28. Kier’s layering rack.	Fig. 29. Kier’s circular layering rack.

CHAPTER IV.

CUTTAGE.

Cuttage.—The practice or process of multiplying plants by means of cuttings, or the state or condition of being thus propagated.

Cutting.—A severed portion of a plant, inserted in soil or water with the intention that it shall grow; a slip.

Cuttings, particularly of growing parts, demand a moist and uniform atmosphere, a porous soil and sometimes bottom heat.

Fig. 30. Hand-glass.	Fig. 31. Small Propagating-box.

Fig. 32. Propagating-box.

Devices for Regulating Moisture and Heat.—In order to secure a uniform and moist atmosphere, various propagating-frames are devised. Whatever its construction, the frame should be sufficiently tight to confine the air closely, it should admit light, and allow of ventilation. The simplest form of propagating-frame is a pot or box covered with a pane of glass. To admit of ventilation the glass is tilted at intervals, or two panes may be used and a space be allowed to remain between them. A common bell-glass or bell-jar (cloche of the French) makes one of the best and handiest propagating-frames because it admits light upon all sides and is convenient to handle. These are in universal use for all difficult and rare subjects which are not propagated in large numbers. A hand-glass or hand-light (Fig. 30) answers the same purpose and accommodates a larger number of plants. A useful propagating-box for the window garden or amateur conservatory is shown in Fig. 31. A box two or three inches high is secured, and inside this a zinc or galvanized iron tray, a, is set, leaving sufficient space between it and the box to admit a pane of glass upon every side. These panes form the four sides of the box, and one or two panes are laid across the top. The metal tray holds the soil and allows no water to drip upon the floor. One of the best boxes for general purposes is made in the form of a simple board box without top or bottom, and fifteen or eighteen inches high, the top being covered with two sashes, one of which raises upon a hinge (Fig. 32). Four by three feet is a convenient size. An ordinary light hot-bed frame is sometimes constructed upon the bench of a greenhouse and covered with common hot-bed sash. Propagating houses are sometimes built with permanent propagating-frames of this character throughout their length.

Fig. 33. Simple Propagating-oven.

Fig. 34. Propagating-oven.

In all the above appliances heat is obtained from the sun or from the bench-pipes or flues of a greenhouse. There are various contrivances in which the heat is applied locally, for the purpose of securing greater or more uniform heat. One of the simplest and best of these is the propagating-oven shown in Fig. 33. It is a glass covered box about two feet deep, with a tray of water beneath the soil, and which is heated by a lamp. A similar but somewhat complicated apparatus is illustrated in Figs. 34, 35, 36. This is an old form of oven, which has been variously modified by different operators. Fig. 34 shows a sectional view of the complete apparatus. The box, A A, is made of wood and is usually about three feet square. L is a removable glass top. B represents a zinc or galvanized iron tray which is filled with earth in which seeds are sown or pots are plunged. C is a water tray to which the water is applied by means of a funnel extending through the box. A lamp, D, supplies the heat. A funnel of tin, e e, distributes the heat evenly. Holes should be provided about the bottom of the box to admit air to the flame. A modified form of this device is shown in Figs. 35 and 36. The water tray, G, slides in upon ledges so that it can be removed, and the heat funnel, L D L, slides in similarly and is made to surround the flame like a chimney. The front side of the apparatus is removable, and the top of the frame, K, is made of metal. The cover for this apparatus is figured in Fig. 36. The ends, a a, are made of wood, with openings, indicated by the arrows, to allow of ventilation. The front and top, g g, are made of glass. The frame-work, c c c, is made of metal. The cover is hinged on, or held with pegs, I I, Fig. 35.

Fig. 35. Modified form of Fig. 34.

Fig. 36. Cover for Fig. 35.

Chauvière’s propagating-frame, an apparatus used by the French, is shown in Fig. 37. It is essentially a miniature greenhouse. The sashes are seen at c c, and above them is a cloth or matting screen. The sides below the sashes are enclosed, preferably with glass. The bottom or floor is moveable, and it is sometimes divided into two or three sections to allow for the accommodation of plants of different sizes and requirements. These sections are raised or lowered and are held by pegs. At a is shown a section of floor elevated, and at the left another section occupying a lower position. Heat is supplied usually by hot water in the tubes, d d. A very elaborate circular French device, known as Lecoq’s propagating-oven, is illustrated in Fig. 38. It is an interesting apparatus, and is worth attention as showing the care which has been taken to control the conditions of vegetation and germination. It is too elaborate for common purposes, and yet for the growing of certain rare or difficult subjects it might find favor among those who like to experiment; and it affords an accurate means of studying plant growth under control. The apparatus is sold in France for about $6. All the portion below the glass top, P p, is made of earthenware. The base, a a, holds a lamp, d; e is a water reservoir to which water is supplied by means of the funnel, j. A vase or rim, b b, rests upon the base, and upon it a plate or disc, c c, is fitted. Above this is a glass top, P p. Air is admitted to the apparatus at i, K K, and between the vase and plate, as at c on the right. The plate contains two circular grooves, g g and h h. In these grooves the soil is placed or pots plunged. The heat circulates in the valleys m and n n n n, and supplies a uniform temperature to both sides of the plants.