gravest defect of the system is, that by it the vegetable world is divided into two classes, namely, Herbaceous Plants and Trees—a division which has no existence in nature. The division destroys

the natural analogies, for the size of a plant has no bearing upon its organisation and structure. In conclusion, the continually increasing number of new species which were unknown in Tournefort’s time, test, in the strongest manner, the defects of his system of distribution. The greater number of vegetable species discovered since Tournefort’s time could not be placed in either of his classes. This defect soon became very apparent, and the system fell by degrees out of favour with’ botanists even among his own countrymen, with whom it had found most favour.

In England the study of plants had taken a more philosophical direction. About the middle of the seventeenth century the microscope was first applied to the study of the organs of plants, and the spiral vessel was detected by Henshaw, and shortly afterwards the cellular tissues were examined by Hooke. These discoveries were followed by the publication of two works on the Physiology of Plants by Malpighiand Grew. They examined the various forms of cellular tissues and intercellular passages in their minutest details, and with an exactness which causes their works still to be recognised as the groundwork of all physiological botany. The real nature of the sexual organs in plants was demonstrated by Grew; the important difference between seeds with one and those with two cotyledons was first pointed out by him. Clear and distinct ideas of the causes of vegetable phenomena were gradually developed, and a solid foundation laid on which the best theories of vegetation have been formed by subsequent botanists.:

About the time when Tournefort was engaged in arranging is system of plants, and when Grew had completed his microscopical observations, John Ray appeared, driven from his collegiate employ-ments at Oxford by differences of opinion with the ruling power® He sought and found consolation in the study of natural history, to which he was naturally attached, and for which his natural powers of observation, capacious mind, and extensive learning, so high!y qualified him. Profiting by the discoveries of Grew and other in 1686 he published the first volume of hisvegetable anatomists, “ Historia Plantarum,” in which are embodied all the facts co?

nected with the structure and organs of plants, with an exposition of the philosophy of classification, the merits of which are better appreciated now than they were in his own days. Ray was careful to guard his readers against the supposition that classification was other than a means of identification. He argued that there was no line of demarcation in nature between one group or order, or even genera, and another, or that any system could be perfect. ‘What, indeed, I said before, I now repeat and — insist on,” he says, “that a system is not to be expected from me, which shall be in every respect perfect and complete in all its parts; which shall so distribute plants into genera that every species shall be included, not one, hitherto anomalous and exceptional, being omitted; and which shall so mark out every genus by its peculiar indications and characteristics, that no species shall be found of uncertain family, so to speak, and referable to many genera. Nor by the very nature of things could this happen. For nature (as is sometimes said) makes no leaps, passing from one extreme to the other, but takes a middle course, between the highest and the lowest, producing a certain order of things of a neutral and ambiguous character, partaking of the qualities of the objects which most resemble them on either side, as if to connect them, leaving it sometimes doubtful to which of the two they belong. Besides, Nature objects to be coerced by the narrowness of any system; and as if to show that her liberty and independence is perfect, she is in the habit, in every part of creation, of producing singular and anomalous species, which form exceptions to the general rule.” While he thus enumerated the true principles of classification, Ray also laid the foundations of the inductive system, which has since distinguished the English school of Botany. He separated flowerless from flowering plants, and he divided them again into Monocotyledonous and Dicotyledonous plants. Forty years after the publication of Tournefort’s system, and

S while Ray was yet pursuing his philosophical investigations, the L system appeared. This new mode of distributing vegetable species was hailed with admiration. Its author, Charles von Linneus, reigned supreme and without a rival till the end of the eighteenth century, and even in our days his partisans are neither

few nor powerless. In Germany, for instance, more than one Book of Character has for its foundation the system of Linnewus, and many school-gardens are arranged after his classification. The system of Linnwus rests upon the consideration of ‘the organs of fecundation—organs almost overlooked until then, but whose physiological functions have since been ably demonstrated. He introduced at the same time a salutary and much-wanted reform into botanical language and nomenclature, defining most rigorously the terms uséd to express the various modifications and characteristics of the organs, and reducing the name of each plant to two words, the first, substantive, designating the genera, the second, adjective, designating a species of the genera. Before Linnzeus, in fact, it was necessary to follow the name of the genera through a whole phrase in order to characterise the species. As the number of species increased, the lengthened phrases were lost to view. It was like the confusion which would arise in society if, in place of using the family name and surname, we were to suppress the baptismal name, and substitute for it an enumeration of many qualities distinctive of the individual; as if, for example, in place of saying Pierre Durand or Louis Durand, we said Durand | the great sportsman, or any other phraseology applicable to the qualities of the individual. The Linnzan or binary nomenclature, then, is one of the great titles to that glory which has been awarded to its immortal author. In the outline of the Linnean system it has been found possible to describe all plants discovered since his time—an irrefragable proof of the great merits of this artificial classification of species. At first Linnzeus divided all known vegetables into two great ae groups: those in which the stamens and pistils are visible, which he called Phanerogames; and those in which these organs are hidden, which he called Cryptogames. These last form only # single class, namely, the twenty-fourth of his system. Among the plants whose assemblage constituted the twenty-three classes, one portion have hermaphrodite flowers; the others _ are unisexua a Plants with true sexual flowers have the male and female orgamS brought together on the same plant. They have a united habi-; tation; they are monaceous, as the name of the class to which ie

the Oak, the Box-tree, Maize, and Castor Oil-plant belongs indicates. They are monaceous, and form the twenty-first of the Linnean classes. The male and female flowers are found upon two distinct individuals. There is a duality of habitation, as the name of the class

Fig. 288.—Linneus.

to which Mercurialis, the Date, and the Willow belong, indicates. This is the class Diece#, and the twenty-second.

A class which is only a combination of the two preceding groups includes the plants which present upon one or many individuals male, female, and hermaphrodite flowers. This is the twenty-third class, said to be Polygamous, on which we find ranged the Ash, the Pelitory, and the Nettlé-tree.

Plants with hermaphrodite flowers have the stamens and the pistils borne the one upon the other, as in the Orchidacee and Aristolochia; they form the twentieth, or Gynandrous class. Sometimes the organs are non-adherent between them, in which case the stamens are free. Sometimes they are adherent. When they are free, they are either equal among themselves or unequal. the stamens are equal, their number determines the first twelve classes in the system. The twelfth and the thirteenth classes are founded upon the number of the stamens and their mode of insertion. The following are the classes:—

Linn2%AN CLASSIFICATION One Stamen in each flower 1st class. Monanpria incurs Cannz). Two Stamens. nd class. Dianpria (Jasmin, Lilac). Three Stamens..... 8rdclass. Trranpra (Wheat, Barley, Iris). Four Stamens..... 4thclass. Tsrranprra (Madder root, Joint Grass). Five Stamens..... Sthelass. Prnranpria (Borage, Hemloc ix Stamens ie 6th class. Herxanpria (Lily of the Mert Lily) Seven Stamens.... 7thclass. Heptanprra (Horse Chesn Hight Stamens.... 8thclass. Ocranpria (Heaths) Nine Stamens..... 9th class. Enneanprtia (Laurel). Ten Stamens. - 10th class. Dgeanpria (Pink, Lychnis). Bisventy Ninetoel Geass llth class. Dopzcanpria (Purple Willow). sions ar) SGatys ¢ 12th class. Tcosannnra (Myrtle, Rose.

eiAnk ~ Norhece2 13th class. Ponyanprra (Anemone, Poppy);

Linnzus founded two other classes upon the inequality of their class), which com- free stamens, the Didynamia (fourteenth prises Thyme, Lavender, Foxglove, and Figwort, plants having four stamens, of which two are short and two long. The Tetradynamia, which comprises the Gilliflower, Cress, and Cabbage, have six stamens, of which four are larger than the others. When the stamens are adherent, the adhiscence has place either at their anthers or filaments. Plants which adhere to the anthers, such as the Corn-centaury, Dandelion, and Ox-eye, belong to the nineteenth class (Syngenesia). Those which unite to the aments form three classes, the Monadelphia (sixteenth), in which all the filaments are united in one body, as in vere thed erensres (seventeenth), in which the filaments 0 bodies, as in the Pea and the Bean; the Pola (cightoonth), in which the filaments are united ™ bodies, as in the Orange.

The twenty-four classes being thus fixed, Linnzus, after some consideration, subdivided each of them—the thirteen first classes according to the number of their styles or distinct stigmata; the fourteenth (Didynamia) by the disposition of their seeds, sometimes bare (or at least what he considered as such), sometimes enclosed in a pericarp; the fifteenth (Tetradynamia) according to the form of the fruit; the sixteenth, seventeenth, eighteenth, and twentieth according to the absolute number of their stamens; the two following from the absolute number of their stamens, and from the manner of their adherence; the twenty-third class (Polygamia), from the distribution of the hermaphrodite and unisexual flowers upon the same plant, or upon two or three different. The nineteenth class (Syngenesia) is divided as follows:—

I. Flowers all fertile, hermaphroditic (Polygamia equalis), Goatsbeard, Lettuce, Thistle.

II. Hermaphrodital flowers, fruitful in the disks; female flowers, fruitful at the circumference (Polygamia superflua), Tansy, Wormwood, Groundsel.

III. Hermaphrodital flowers, fruitful in the disk; neutral flowers, sterile at the circumference (Polygamia frustranea), Centaury, Sunflower.

IV. Hermaphrodital flowers, sterile in their disks; female flowers, fertile at the circumference (Polygamia necessarea), Marigold.

V. Flowers provided with a proper and clustered calyx, under a common calyx (Polygumia segregata); separated flowers (Monogamia), Lobelia, Violet:

This classification of plants has received the name of the artificial system, because it groups the species according to a small number, and not from the whole of their characteristics; in short, it rather permits one species to be distinguished from another, than makes each known in an intimate manner. It insists much upon their differences, little upon their resemblances. Between species thus compared, only one essential analogy may exist. The Rush takes place beside the Barberry, because each of these plants have six stamens and only one style. The Vine is ranged beside the Periwinkle, because they each have five stamens and one style. The Carrot is allied to the Gooseberry,&c. There may not be between the plants thus compared any natural bond, any essential characteristic,

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