Botany.

is very extensive, containing economic, systematic, and archeological collections. Most of the gardens in Germany are equipped for all lines of botanical research, although it is very common for particular attention to be paid to some special line of work. The "Jardin des Plantes," of the Museum of Natural History at Paris lies in the heart of the city and contains very complete laboratories, herbarium, and library, while the plants under cultivation for systematic work present a good assortment of species. Other gardens outside the United States which deserve special mention both because of their equipment and because of their valuable contributions to botanical science are the Botanical Gardens of Geneva, the Botanical Gardens of the university of Vienna, the Royal Botanic Gardens of Edinburgh, the Royal Botanic Gardens of Dublin, the Brussels Botanic Gardens, the Imperial Botanic Gardens at St. Petersburg, the Botanic Gardens of Jamaica, Munich, Würzburg, Tübingen, Stockholm, Copenhagen, Upsala, Zurich, Ceylon, and Calcutta.

The first B. G. in the United States was established by John Bartram in Philadelphia in 1728 and it still remains in a modified form. In 1801 Dr. David Hosack, Professor of Botany and Materia Medica in Columbia college, established a B. G. in New York City and for ten years this garden was directly under the control of its founder, who succeeded in forming a large collection of plants. At the end of this time the garden became state property and was subsequently granted to Columbia college, but owing to a lack of funds it was finally abandoned. Another fruitless attempt to establish a garden was made in connection with the Transylvania university at Lexington, Ky., about 1824, but it soon ceased to exist. The B. G. in connection with Harvard university at Cambridge, Mass., was founded in 1805 and comprises about seven acres of ground under cultivation and a small greenhouse. In this garden are cultivated about seven thousand species, mostly native, and connected with the garden is the famous herbarium and library in which Asa Gray accomplished his work on North American plants. From the laboratories connected with this garden, but located in the university buildings, a short distance away, have been published a large number of important works on the morphology of cryptogams. In this connection should be mentioned the Arnold Arboretum of Harvard university located at Jamaica Plain, Mass., and entirely independent of the B. G. This Arboretum was founded in 1870 through the generosity of Mr. James Arnold, of Providence, R. I., and comprises about two hundred and fifty acres of which one hundred and sixty are planted to trees and shrubs. It has a museum, herbarium, and library, which render it a most satisfactory place for the study of forestry. The B. Gardens connected with the Department of Agriculture at Washington include a large area of land and an extensive range of greenhouses. The herbarium, deposited with the National Museum, is already large and rapidly increasing. There are several laboratories from which are issued Bulletins of the various branches of the Department. The Missouri Botanical Garden at St. Louis, formerly known as Shaw's Garden, was established in 1889 in accordance with the will of Mr. Henry Shaw, who bequeathed for this purpose about six hundred and seventy acres of land together with other property in and near St. Louis. The garden proper comprises about fortyseven acres, is maintained by the proceeds from the remainder of the land, and is operated in connection with Washington university at St. Louis, which has a School of Botany endowed also by Mr. Shaw. The garden facilities are very good for research in systematic botany, in which direction the library is also exceptionally strong. The herbarium is very large and valuable including the collection of Bernhardi and Englemann. The living collections afford unusual opportunity for morphological, anatomical, and physiological studies. The B. G. connected with the Michigan Agricultural college at Lansing, Michigan, was established in 1877 and consists of about three acres under high cultivation aside from the arboretum and decorative grounds. Connected with the garden are several small greenhouses, an herbarium, a good botanical library and several large, well equipped laboratories. The university of Pennsylvania has also a small B. G. of about three acres near its buildings in Philadelphia. The garden, together with the extensive and well equipped laboratories, good library, and herbarium, affords special opportunities for reseach in morphology and physiology. A B. G. was established several years ago at Berkeley, California, in connection with the university of that state and is a valuable addition to the botanical department which is supplied with well appointed laboratories, good library and large herbarium. In 1893 a garden was established in the south side of Buffalo, N. Y., and was formerly known as South Park, but is now called the Buffalo Botanical Garden. It contains a number of greenhouses and nuclei of a library and an herbarium. A small garden has been started on the campus at Ann Arbor, Michigan, in connection with the botanical department of the state university. A garden has also been established on the campus of Smith college, at Northampton, Mass. The most recent large garden is the New York Botanical Garden, established in 1891 by an act of the Legislature, through the efforts of the Torrey Botanical Club of New York. Owing to a flaw in the legislation no active steps were taken to carry out the plans until 1894, at which time the Commissioners of Public Parks of New York City were authorized to set aside two hundred and fifty acres in Bronx Park for garden purposes. Bonds were also issued to the extent of five hundred thousand dollars for the purpose of constructing the necessary buildings, for which ground was broken in 1898. Owing to the great diversity of soil and other conditions the garden is peculiarly fitted for the growth of an extensive flora. A co-operative

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arral gement exists between this garden and Columbia university, whereby the university herbarium of over six hundred thousand species and a large part of the library will be deposited in the garden, where most of the graduate work in botany will be carried on. BOTANOMANCY, divination by means of plants. See DIVINATION.

BOTANY (Gr. botane, a plant) is that branch of natural science which treats of plants. Undoubtedly this science was first studied simply for the purpose of determining which plants were suitable for food, so that even before any record was made of their appearance, structure, distribution, etc., they were divided into three classes, nutritious, nonnutritious and poisonous. Another incentive which led to an early study of plants was the necessity for substances possessing healing or curative properties, with which it was the belief among the ancients that the gods had endowed particular plants. In ancient Greece a guild was formed for the purpose of collecting and preparing such plants or plant parts as were supposed to be curative, and the information thus gained constituted the first botanical literature, much of it being legendary and fanciful. As late as the beginning of the sixteenth century plants were looked upon and studied almost entirely from a utilitarian point of view. In searching for signs that might reveal the uses of the various species of vegetation to man, some thought they saw in the leaves, fruits, seeds, etc., of certain plants a close resemblance to organs of the human body. This led to the so-called "Doctrine of Signatures," based upon the belief that a heart-shaped blossom would restore to health a diseased heart, that a livershaped leaf would cure all hepatic disorders, etc. This theory reached its climax under Paracelsus, a Swiss alchemist who lived in the early part of the sixteenth century,-the idea continuing to flourish, however, until the end of the seventeenth century, and still surviving among certain classes of people in all countries. It is true that in addition to these necessities of life that caused men to study the vegetable kingdom, a love for the beautiful led to the observation of plants for purposes of ornamentation. Wild flowers and leaves were first used for this purpose, but later plants were cultivated for the sole object of satisfying man's æsthetic taste. This incentive to cultivation of plants still exists, of course, and, while many beautiful and interesting plant forms have been developed under cultivation, the possibilities in this direction are by no means exhausted. Botanists early recognized the fact that in order to refer to known plants in an intelligent manner, a careful des cription of their structure and appearance was necessary. One of the earliest botanical writers was Theophrastus, who lived about 300 B. C., and who wrote a "Natural History of Plants," a work founded largely upon observations of Greek physicians and agriculturists, and comprising about 500 plants, most of which possessed economic or medicinal values. Dioscorides, a Greek writer, brought out in the early part of the first century a Materia Medica in which about 600 plant species were described. Pliny also devoted some time to B. and described more than 1000 species, most of his work in this field being compiled from other writers, however, and considered of little value. In spite of the great disadvantages under which early botanists worked, their knowledge of plants was wonderful; for example Theophrastus recognized the sexes of plants as did the other early writers also, although it does not appear that they had discovered the sexual organs. During the middle ages no advances were made in botanical science, in fact but little attention was paid to the subject except in so far as the economic and medicinal values of the plants previously discovered were concerned. In the early part of the sixteenth century, however, the study of B. was resumed, the old Greek writings on plants were brought to light, a desire for investigation was aroused, and an eager search was made for all indigenous plants. This resulted in the appearance of numerous botanical works, but unfortunately plants were described and discussed in the order in which they happened to be found with only here and there a faint effort to arrange similar plants in groups. It appears also that no attention was paid to geographical distribution, but those plants taken to Europe from the New World were described along with the native species. This mistake on the part of botanists of those times arose from the fact that they believed that the plants in all countries were alike, and that when a description was once written it was necessary only to find the plant corresponding to it. Among the best known early German botanists were Brunfels, Bock, and Fuchs, who lived between 1495 and 1566. These men abandoned gradually the old Greek and Latin writings and devoted themselves to the direct study of plants. In the latter part of the same century, Charles de L'Ecluse, a Belgian, freed himself entirely from the controversies over names, gave up the utilitarian idea, and endeavored to become acquainted with the whole flora of Europe, for which purpose he traveled to all parts of the continent. Other botanists caught the same spirit and journeys were made to every quarter of the known world with the result that a very large amount of material was collected and many new plant forms were discovered. The necessity for some method of classification and for shorter names became more and more urgent. The fact that the names In 1583 an attempt was already given were intended to describe the plant led to much difficulty, since some of the plants had names consisting of a dozen or more words. made by Andreas Cæsalpinus to classify the 1520 plants which up to that time had been described. He divided them into fifteen classes, chiefly according to the nature of their fruit, although the form and arrangement of leaves and other striking characteristics were not neglected. After nearly a century the principles established by

Casalpinus were taken up and carried forward by Morrison, Ray, Bachman and others. Of these Ray deserves especial mention for the zeal and the fairness with which he pursued the subject. In spite of his keen sense of likenesses and differences, however, he persisted, as his predecessors had done, in classifying the known plants as woody and herbaceous forms. He made one marked advance in observing that some embryos have two leaves while others possess only one, although he did not succeed in separating clearly the monocotyledons and dicotyledons, as they are at present recognized. It remained for Linnæus, a Swedish botanist who was born in 1707, to arrange the material and the facts which had accumulated, and to establish the classification of plants upon a different basis. In his travels and study his attention had been called to the sexes of plants, and when he began his independent research he paid especial attention to the reproductive organs. He not only recognized stamens and pistils, but divided the former into filament, anther, and pollen, and the latter into ovary, style, and stigma. He also carried the naming of other parts farther than had been done previously, recognizing root, stem, leaf, bract, calyx, corolla, etc. Furthermore, he introduced short names and concise descriptions for individual plants, and gave to the two main divisions of the vegetable kingdom the names Phanerogamia, and Cryptogamia. The former he divided into twenty-three classes, depending upon the number, arrangement, cohesion, and relative length of stamens. These classes were subdivided into orders according to the nature of the pistil, in which the number of styles was the important consideration, the orders being further subdivided into genera. Cryptogamia were divided into Ferns, Mosses, Algæ, and Fungi, although but little attention was paid at that time to any of the forms below flowering plants. This classification, which was based upon only a few characteristics, mainly the sexual organs, is sometimes known as the sexual system and is artificial in comparison to a natural system based upon all the characteristics of the plant. Linnæus recognized later the weakness of his classification and undertook to prepare a natural system, but succeeded in finishing only a small portion of it. He found many followers in all parts of the civilized world, but many of them hindered rather than helped the cause of botanical progress, either by their long discussions over classification, or by lack of appreciation of the scientific value of their work. Among the followers of Linnæus was Bernard de Jussieu, who made some improvements in naming and in grouping plants, and whose work was carried on by his nephew Antoine de Jussieu. The latter was the first to call attention to the distinguishing characteristics of families, a very important and difficult step, as it was the beginning of the separation of the vegetable kingdom into main and subordinate groups. He separated plants into Acotyledons, Monocotyledons, and Dicotyledons, under the first division placing one class, the cryptogams; under the second, three classes depending upon the insertion of stamens; and under the third, four subdivisions based upon a study of petals, these four subdivisions being separated further into twenty-one classes according to the insertion of stamens and petals. The twenty-five classes thus formed Jussieu divided into one hundred subdivisions which he styled families, and to which he assigned names, many of these being still in use. This system was modified and improved by Pyrame de Candolle, who lived in the latter part of the last and the beginning of the present century, and who gave his attention to all departments of B., using the results of morphological and physiological investigations to aid in a more perfect classification. He divided the vegetable kingdom into two parts, viz., vascular and cellular plants. In the first class he placed those plants which have cotyledons, and separated them into two divisions, Dicotyledons or Exogens, and Monocotyledons or Endogens. The dicotyledons were again divided into plants whose flowers possess both calyx and corolla, and those whose flowers have but a single floral envelope. Under monocotyledons were placed true monocotyledons and vascular cryptogams such as ferns, etc. In the cellular or acotyledonous division were placed Mosses and Thallophytes. This classification, which appeared in 1819, was based upon the principles of comparative morphology, i.e., De Candolle and his followers sought to establish relationship by resemblances in structure. Changes were made in systems of classification as new facts and new relationships were brought to light. Robert Brown established morphological relations in the organization of seeds of dicotyledons and monocotyledons, and also called attention to the differences between the flowers of conifers and those of other plants, pointing out the fact that the female flowers of conifers are naked ovules, and thus establishing these plants as a separate class.

Since the organs of reproduction and the processes and results of fertilization are such important factors in gaining a better knowledge of the vegetable kingdom for purposes of classification, it will be well to look briefly at the treatment of this subject by early botanists. By Aristotle and others fertilization was regarded as a process of nutrition. Theophrastus recognized a difference in the behavior of the flowers of male and female palms, i.e., he observed that certain of the trees produced fruit while others bore only flowers. Other naturalists observed that plants bearing male and female flowers must be brought near each other in order that the latter produce seeds. It was not until 1682, however, that stamens were recognized as the male organs of generation, and even then this idea met with considerable opposition. Although such men as Grew and Malpighi concerned themselves with this question and even observed the pollen in the anthers, they did not investigate the subject experimentally. Little was

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known therefore in regard to the sexuality of plants until Camerarius engaged in the experimental solution of the problem in 1691. It is true that the process of dusting flowers had been practiced even before the time of Theophrastus, but how the fertilizing matter reached the ovule, and indeed whether the dust or pollen was absolutely indispensable, were unsolved questions. Camerarius observed that plants bearing only pistillate flowers sometimes produced fruit but with undeveloped seeds. He also found Of the naturalists immediately by experiment that when unripe stamens were removed from flowers possessing both stamens and pistils, perfect seeds were rarely obtained. following Camerarius, some still rejected the idea of sexuality, others continued to investigate the necessity of pollen, while others accepted the theory of sexuality and reThe first theory in regard to garded stamens as the male organs of reproduction, concerning themselves with the problem of how the fertilizing matter reached the ovule. this latter question was brought out about the middle of the last century, and was based upon observations seeming to show that the pollen grain burst upon the stigma and that the granules contained found their way down through the style to the ovules, there developing into embryos. Early in the present century (1823) Amici accidentally discovered pollen tubes while examining the hairs on the stigma of Portulaca, and seven years later had the satisfaction of tracing a pollen tube into the ovary and of observing that one pollen tube finds its way into each ovule through the opening called the micropyle. Other observers had noticed the pollen tubes but did not trace out their functions, while many investigators gained false notions in regard to their origin and importance. For instance, Robert Brown believed that the tubes started in the ovary and grew out toward the stigma, perhaps as the result of fertilization. Schleiden thought he saw the end of the pollen tube enlarge after it had reached the embryo-sac and gradually develop into an embryo, from which he concluded that the embryo-sac was only the place in which the embryo was developed from the pollen tube. This theory was adopted by many naturalists, but was strongly opposed by Amici. In 1846 the latter established his views, viz. that the egg cell is present in the embryo-sac before the arrival of the pollen tube, and his observations were confirmed by experiments of von Mohl and Hofmeister the following year. Hence, before the middle of the present century there was no doubt in the minds of botanists in regard to the sexuality of flowering plants, nor in regard to the method by which fertilization is accomplished. A few observations had also been made in the latter part of the eighteenth century along the same line in regard to cryptogams, but very little was known with certainty respecting their methods of propagation. Investigators were looking for those organs in flowerless plants which should correspond to anthers and pistils in flowers, and in mosses they had already observed the antheridia and the archegonia which were regarded as stamens and ovaries. Many mistakes were made before the true reproductive As the improved compound organs in ferns were discovered; for example, the stomates, glandular hairs, and indusia were regarded by different botanists as anthers. microscope aided in the solution of the sexual process in flowering plants, so it was indispensable in the study of cryptogams. As early as 1803 conjugation had been observed in Spirogyra, and this was looked upon as a sexual act in these plants, the same process being observed in molds in 1820. Spermatozoids of mosses were seen first in 1822, and those of Chara in 1828, although they were at that time thought to be some lower form of animal life, and it was not until 1837 that their real character and funcIn 1844 the spermatozoids of ferns were discovered, but up to tions became known. this time the female organs of reproduction had not been found in any of the cryptogams. While Count Lesczyc-Siminsky in 1848 was examining the prothallia of ferns, which had hitherto been looked upon as the cotyledons of these plants, he discovered both antheridia and archegonia. This discovery was followed by many erroneous ideas in regard to the method and results of fertilization, but a correct account of the process was given by Hofmeister in 1849, and his observations were confirmed by others in the following year. When it was fully established that fertilization consists in the fusion of two naked bodies of protoplasm, the spermatozoid and the egg cell, the process which had been observed in Spirogyra and other forms became more intelligible. Thus botanical knowledge in regard to sexual reproduction has been advanced until the history of the process is known for nearly all divisions of the plant kingdom. It is true The knowlthat sexual reproduction has not been observed for all plant forms, and indeed it is believed by some botanists that the process does not take place in all cases. edge gained in regard to methods of reproduction has aided greatly in improving and extending systems of classification of plants.

Another important factor and one which has contributed largely not only to a better knowledge of plants individually but also to the relationships which exist between them is the study of their microscopical structure, usually known as Histology, Inner Morphology, or Microscopical Botany. It began with the discovery of the cell in 1667 by Robert Hooke while examining thin layers of cork and other substances for the purpose of testing the magnifying power of some lenses, but the first real knowledge of the inner morphology of plants was due to the efforts of Malpighi and Grew a few years after cells were discovered. Hence at the end of the seventeenth century it was known that plants are composed of small room-like spaces filled with fluid among which bundles of long tubes of various kinds are to be found. Soon after the middle of

the eighteenth century Wolff and others endeavored to show that the vessels and ducts originate in cells, but this point was not fully established until the beginning of the present century when Treviranus saw that young cells arrange themselves in rows, and become transformed into elongated tubes by the breaking down of their separating walls, a fact afterwards confirmed by the investigations of von Mohl. Up to this time investigators had concerned themselves for the most part with the structure and arrangement of tissues as they appeared in fully developed plants, but in 1838 Schleiden undertook to explain the mystery of cell formation. He believed that the cell nucleus, which was discovered in 1833 by Brown, would furnish the key to the origin of cells, and as he subsequently discovered that the nuclei are present in young cells he thought that nuclei and cell formation must be closely related. The question was further investigated by Schwann and the theory of cell formation thus established is known as the Schleiden-Schwann theory. They considered that the cell was a small vesicle with a firm membrane, and that it contained fluid contents of which the membrane was looked upon as the essential part which had the power of regulating the metabolic processes within the cell. They believed further that young cells were formed from the mother cells by a process of crystallization. This theory was readily accepted by a number of scientists, and naturally led to close study of the cell-wall or membrane in regard to its nature and method of growth, which resulted in the establishment of the theories known as apposition and intussusception. Prominent among the investigators of the Schleiden-Schwann theory were Nägeli and von Mohl, who in 1844 recognized that the cell contents were more important than had been supposed. They distinguished the primordial utricle, and in 1846 von Mohl gave to the slimy cell contents the name protoplasm. As the importance of the cell contents became more evident a strong opposition to Schleiden's theory was inaugurated, finally resulting in its overthrow and the establishment of the protoplasmic theory now accepted by all scientists. Although many investigators were actively engaged in the solution of this problem and were instrumental in breaking down the old cell theory and in establishing the new, credit is due chiefly to Max Schultze for bringing together the facts and formulating a theory based upon the idea that a cell is a small mass of protoplasm endowed with life without reference to the cell membrane. It is true that the protoplasmic theory has been modified within the latter half of the nineteenth century, but the modifications are due to a better understanding of the structure and functions of the cell parts and of their relation to each other, so that a cell is no longer considered a simple mass of protoplasm, but a mass of protoplasm containing differentiated portions such as nucleus, centrospheres, and for green cells chromatophores. The study of the minute structures of plants, like the study of sexuality and methods of reproduction, has had a marked influence upon classification.

Among the various classifications which have appeared in the latter half of the nineteenth century is one established by Sachs in 1874 which is both interesting and instructive. He divided the plant kingdom into four parts, viz. Thallophytes, Musci, Vascular Cryptogams, and Phanerogams. Thallophytes were again divided into Protophytes, Zygospores, Oospores, and Carpospores. Under Protophytes were classed those simple forms like yeast, bacteria, and the blue-green algae which are scarcely to be distinguished from the lowest forms of animal life. Zygosporeæ included those forms which, as their name implies, produce resting spores and embraced forms that in general appearance are somewhat different from each other, such as Myxomycetes, Volvox, Spirogyra, etc. Oosporeæ included those plants in which a large cell, the oogonium, is developed, this cell containing one or more rounded masses of protoplasm known as oospheres which are subsequently fertilized by a special cell of smaller size called an antheridium. The result of the union of these two cells is an oospore from which a new plant may develop. Under this class were included Peronospores, Vaucheria, Fucaceæ, etc. Under the name Carpospores were included all those forms in which the result of fertilization is the formation of a so-called sporocarp, usually consisting of two distinct parts, viz., a fertile portion that forms either directly or indirectly a larger or smaller number of spores; and a sterile part developed from cells adjacent to the fertile cells and so constructed that the latter are covered and protected by the former. This class like all the preceding classes included both green and colorless forms among which may be mentioned chara, red seaweeds, ascomycetes, basidiomycetes, etc. Although Schwendener had already pointed out that lichens are composed of fungi and algæ living in a peculiar parasitic relation with each other, Sachs classed these forms among the carposporeæ because the fungus part of most lichens is composed of ascomycetes. The other divisions of the vegetable kingdom with their classes as given by Sachs are practically the same as in the more recent systems, and will therefore be considered later. This classification of Thallophytes as given above has been adopted in a more or less modified form by Bessey and others. One of the later systems which has met with favor among botanists generally is that given by Schenck in Strasburger's Lehrbuch. This system is based upon the classification given by Braun and further developed by Eichler and others. It divides the plant kingdom into Cryptogams and Phanerogams, the former being subdivided into Thallophytes, Bryophytes and Pteridophytes, the latter comprising Gymnosperms and Angiosperms. Cryptogams include a great variety of forms, but are characterized, as