are found, until they become winged insects and eat their way out. The Rose Willow is so called from its bearing an excrescence like a rose at the end of its branches, in consequence of the puncture of an insect.

Some diseases of the skin to which vegetables are subjected, are not yet so well understood by botanists. There is one kind of honey-dew to which the Beech in particular is liable, which in consequence of an unfavourable wind covers the leaves with a sweet exudation. The Hop, according to Linnæus, is affected with honeydew and rendered unfruitful, in consequence of the attacks of a certain caterpillar on its roots. The blight in corn is now considered to proceed less frequently from disease in the plant itself, than from the growth of a minute Fungus upon its seed and herbage.

THE SYSTEMATICAL ARRANGEMENT OF PLANTS.

When we look out upon our fields and hedges, and see them thronged with flowers and foliage endlessly variable, differing in scent, in form, and colouring, scarcely any one among them exactly like another, it seems to us but a beautiful confusion, in which we may indulge our admiration, but should be lost in any attempt to understand it. Yet in nature is no confusion. The minutest hair on the minutest flower has not been placed there to no purpose. The purpose may be beyond our search indeed, and not seldom is so-but our discoveries with respect to nature's more secret operations and contrivances, have been sufficient to convince us, that what we cannot discover is equally curious and important. And in proportion as science has advanced, more order and systematic arrangement have been discovered in every sort of natural production.

But whether or not any natural arrangement can be discovered, it is necessary to make one ere the study of any class of objects can be pursued with success. For this purpose the various subjects of Botanical research have been divided and subdivided according to the most

striking resemblances or differences in their structure and appearance. In part nature has done this for us. Though there are many kinds of Rose or Geranium we have never seen, we should immediately on being presented with them, give them their name as such: thus placing them without examination in the class of flowers to which they belong. A habit of closer observation will enable us to do this with a large proportion of the wild-flowers which may now appear to us without order or resemblance. The invariably unequal petal that distinguishes the beautiful little flowers of the Veronica, and the long, stalklike germen that immediately tells us we have found an Epilobium, are but instances of the many facilities nature has afforded in the classification of our subjects and the aid we shall receive from observation, in making use of the botanical arrangements provided for us by those whose previous researches have made the study so easy. But as the distinctive characters of a plant are not always so striking, a regular method of examining and distinguishing them is necessary.

The method now adopted, we believe almost universally, is that of Linnæus, which we proceed to explain : its use and purport being only to enable us, on finding an unknown flower, to discover what it is, by first determining the Class and Order to which it belongs; thence the Genus, and finally the Species, which makes us acquainted with the Botanical and English name usually assigned to it.

The first division of vegetable productions made by our botanists is that of Classes. Some, after Linnæus, make the Classes to be twenty-four, but we prefer to follow the arrangement of Withering, which makes them only twenty. These Classes are distinguished by the number, length, or situation of the Stamens. The terms used for them are the following, which we recommend the student to commit to memory. We shall now only enumerate them, meaning to give a particular description of each in a future number.

14. Didynamia....

Receptacle

Stamens 4-2 long and 2 short

15. Tetradynamia.... Stamens 6-4 long and 2 short

16. Monadelphia All the Filaments united

....

ers compound

Flowers inconspicuous

Of the twenty classes here enumerated, we observe that the first eleven classes are distinguished merely by the number of Stamens found in each flower. The twelfth and thirteenth each contain an unlimited number, but are distinguished from each other by the Stamens of the twelfth being fixed on the Corolla or Calix, so that they will come off with it if the flower be dissected, while in the thirteenth they are fixed on the Receptacle. The fourteenth and fifteenth are known by the unequal length of their Stamens. The sixteenth differs from all these by the Stamens being so united together as to form a tube of the Filaments, the Anthers only being separate—as in the Geranium. In the seventeenth they are united into two parcels, but not very distinctly; yet this class is easily distinguished by the shape of the flower, which is papilionaceous, like the Pea. The eighteenth has the Stamens divided into more than two parcels. The nine

teenth class is already known by the uniting of the Anthers into a tube and by the compound flower. The twentieth, though difficult to study, is easily distinguished from the

The flowers are either too minute to be dissected, or not distinguishable at all from the rest of the plant. Such are Mushrooms, Ferns, and Sea-weed.

It is our intention hereafter to give a fuller explanation of each class, with engravings, and as far as possible an explanation of what may seem difficult in each. The whole vegetable world being thus divided into twenty classes, each class is itself divided into orders. The order of a plant is in some classes determined by the number of the Pistils, in others by the Seeds or Pods, in some even by the Stamens-but we prefer to defer the explanation of these till we take each class separately into examination. Each order contains many Genera, which is the third division; and again each Genus is divided into different Species. We hope to make these repeated divisions quite plain, by dissecting the flower we have given in the plate; but if a living specimen is at hand, it will still better assist the learner...

Having gathered our specimen of an unknown flower, with due attention to the situation and manner of its growth, careful also to gather it quite to the root, if the root itself cannot be taken up, we examine the flower first with a view to discover in what class it is ranged; for this purpose we should always be provided with more flowers than one, that we may freely dissect them. That which we have chosen for an example is a large and beautiful pink flower very common in our hedges. The first thing we examine is the Stamina-we find them, (Plate 3. Fig. 1), with the filaments (a) so distinctly united into a tube, the anthers (b) attached to the top, and the pistilla (c) issuing from the midst, that we cannot doubt its being Monadelphia, Class sixteenth, of which the distinctive character is that all the filaments are united. This point determined, we examine the Pistilla (c) and by counting find them to be more than ten-which deter