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Popular Science Monthly/Volume 41/August 1892/Beginnings in Botany

BEGINNINGS IN BOTANY.
By BYRON D. HALSTED, Sc. D.,

PROFESSOR OF BOTANY IN RUTGERS COLLEGE, NEW JERSEY.

MUCH has been said, largely in a theoretical way, concerning the general question of university extension. Various experiments have been made, and by another year definite plans will be matured for the popular presentation of many of the subjects that come within the scope of the extension movement as now understood by those who have had the most to do with the scheme for the education of the masses.

The writer has recently finished a brief course in botany, and, as the method pursued differed in some features from any previously followed, there may be sufficient reason, in this, for presenting an outline of the ground covered and the ways and means employed for bringing the subject to the attention of a popular audience.

The course consisted of six meetings, and the average attendance was fifty. Each session extended over two hours, namely, from four until six in the afternoon of successive Fridays for six weeks in late spring. The first hour of each exercise was devoted to a lecture, and the following were the subjects considered: (1) The Seed, its Origin, Structure, and Uses; (2) the Stem and Root; (3) the Leaf, its Structure and Function; (4) the Flower, its Form and Use; (5) the Fruit—Kinds and Functions; (6) Ferns, Mosses, Algæ, and Fungi.

A full outline of these lectures was furnished each pupil in a sixteen-page syllabus, and the points covered were fully illustrated by means of papier-maché models of various sorts of plants, by numerous wall-charts, and, best of all, by a large number of living specimens.

The lecture served as an introduction to the class exercise which it immediately preceded. In this latter each pupil was furnished with a seat at a table and provided with specimens upon which to work. As before stated, the first lecture was upon seeds. This embraced the whole question of germination, and for a portion of the class-hour attention was given to the study of seedling plants, each pupil having specimens of young corn and bean plants for comparison. These two seedlings, because representing the two great types of flowering plants, namely, the exogens and endogens, made it possible to illustrate the leading features of each by contrast. Sketches and descriptions of these were made during the hour by each pupil. Recognizing the fact
Student's Name________
 
 1. Is the FLOWER—
Perfect?
Complete?
Regular?
Symmetrical?
 2. Is the CALYX—
Gamosepalous?
Polysealous?
Free?
Adherent?
 3. Is the COROLLA—
Gamopetalous?
Polypetalous?
Free?
Adherent?
 4. How many STAMENS?
Free.
Adherent.
Anthers.
Innate.
Adnate.
Versatile.

Filaments.
Shape.
Length.
 5. How many PISTILS?
Free.
Adherent.
Stigma.
Style.
Ovary.
Cells.
Placentation.
Ovules.
Number.
Position.
Fruit.
Seed.
 6. INFLORESCENCE.
 7. LEAVES.
Arrangement.
Venation.
Shape.
Base.
Apex.
Margin.
Petiole.
Stipules.
 8. STEM.
Exogenous.
Endogenous.
 9. COMMON NAME.
10. SCIENTIFIC NAME.

Fig. 1.
that seeds come from flowers, and that the time for the course was short, a half-hour was spent in the study of a very simple flower, the spring lily (Erythronium americanum). For this purpose a blank was provided, shown in part in Fig. 1, and before the session was through the various parts of a blossom were learned. Similar blanks were given the pupil for home study, and, before leaving, each was handed a box containing five kinds of seeds—namely, corn, bean, flax, clover, and timothy—with directions for sowing in a box or flower-pot for individual home study. In addition to this the first twenty pages of Gray's Revised Lessons were assigned for study. The public library of the city was equipped with a full list of reference-books in botany at the beginning of the course.

The second lecture embraced a consideration of the stem and root. The chief differences between these two plant-members were pointed out and illustrated with specimens. Buds, as to their nature, structure, arrangement, etc., were dwelt upon, followed by many illustrations of various kinds of stems, such as tendrils, spines, and numerous forms of subterranean stems, like potato tubers, bulbs, and root-stocks of many plants. Various kinds of roots were shown, particular attention being paid to the functions of these underground portions, followed by an exposition of the way in which the soil constituents are taken up by plants.

The first half of the class exercise of the second day was occupied with a study of the buds of the horse-chestnut, in connection with more advanced specimens of the same species in which the buds have unfolded, and the scales, leaves, and flower-cluster were fully shown. After drawings were made of these, and a study of the corn-stem to illustrate the second type of stem (endogen), the remaining portion of the hour was occupied with work on two flowers of the more simple types gathered from the fields and furnished in abundance. Specimens of these plants, with blanks to fill in connection with the study of them, were taken home by the pupils.

At this session a report of the daily observations of the seedling bean, corn, flax, clover, and grass was submitted, and this work in the home garden continued. Twigs were assigned for study during the coming week, including a potato tuber that had been planted by each pupil the week before.

In the third lecture the subject of leaves was considered as to parts, arrangement, types of framework (venation), simple and compound forms, and various peculiar kinds of leaves were shown, as pitchers, fly-catchers, etc. It was in this lecture that some of the physiological principles of vegetation were brought out, including the taking up of the soil-water, its passage to the leaves, and the manufacture there, under the influence of sunlight, of the various compounds, as sugar, starch, and oil, that may be afterward employed in various ways in the economy of the plant.

The microscopic structure of the pulp of the leaf was shown by diagrams, and an insight was given into the cellular formation of tissues and their combinations into tissue systems. A very large number of kinds of leaves freshly gathered were exhibited to illustrate the many terms concerning foliage used in the classification of plants. In size and shape these varied through all gradations, from the mere scales of the asparagus and conservatory "smilax" to those of the garden rhubarb; and of the compound sorts, from the barberry with a single leaflet to those of the columbine.

The class-hour was devoted to the study of three plants, the flowers of which illustrated as many widely separated types. Thus the wistaria gave large peculiar blossoms of the pulse family, and in this connection a papier-maché model of the pea was dissected before the class, thus fully illustrating the several parts, even to the coats and embryo of the forming seeds, by means of a separate model of an enlarged pea-pod.

In the fourth lecture the flower was considered, and, while the parts had been previously learned in class-work with specimens, the functions of the various organs were now explained by means of diagrams and specimens. The many ways in which the pollen of one flower is brought to the pistil of another were illustrated, and the fact that close fertilization is the exception and not the rule emphasized. The pupils were made familiar with the various forms of flower arrangement by seeing the living examples. Perhaps fifty kinds of plants in bloom were shown to illustrate not only inflorescence but the form and union of the several parts of individual flowers.

During the second hour attention was called to the analytical key as an aid in classifying plants, and the class as a whole was instructed by carrying three plants successively through the key to the species. At the same time blanks were filled which made a record of each student's results of inspection. Pupils were now ready to take the simpler plants and classify them at home, which was done to a large extent by some members of the class.

The fifth lecture was a treatment of the general subject of fruits. The subject was illustrated by means of a large list of fruits, freshly gathered from the field, supplemented with several sorts procured at the store. Various seed-vessels may be found in the spring that illustrate fully the methods of opening of the dry fruits for the scattering of seeds, and these were drawn upon at this seemingly unseasonable time for the study of fruits with excellent results. The methods of pressing and mounting plants were practically illustrated at the close of the hour, and a portion of a herbarium placed within reach for inspection.

During the class-hour fresh specimens were supplied, and each pupil worked independently in large part in determining the species. Particular attention was paid to fruits, and the twisting of the cranesbill awns, for example, was seen by all. The sensitiveness of the stamens of the barberry was likewise observed by the class during the hour.

For home work, besides the twenty pages in the text given for each lesson, ten questions were asked in the syllabus, the answers to which were handed in at the next meeting, along with the reports upon "Topics for Study," likewise given in the syllabus. Thus, under Fruits, two of the questions were "(4) In what particular does a strawberry differ from a rose fruit? (6) Of what advantage to a plant that its fruit is a highly colored berry?" Under "Topics for Study" one requirement was to "make drawings of a cross-section of an orange and an apple."

The sixth and last lecture of the course considered the flowerless plants, or those forms of vegetation which are propagated through spores and not by means of seeds.

While upon the ferns, several species in quantity were in the hands of the members of the class, and the method for classifying them gone through with while the descriptive terms necessary for this were being considered. Plates covered with fresh mosses, some sterile and others in fruit, were passed around, while the manner of spore-formation was illustrated by a large papier-maché model of the moss capsule, that was dissected before the class. Various groups of fungi were considered, some of the larger forms shown, as the toad-stools, shelf fungi, and the like, and several rusts were also exhibited. The lecture and the course closed with a consideration of the various groups of sea-weeds, specimens of which were handed around the class. The leading books upon the several families of cryptogams were shown, especially those illustrating the subject by means of large plates.

It was announced in the syllabus that the examination for certificates would be held in the following autumn, and at the close of the last lecture a conference was held with the candidates, about twenty-five, and a short preliminary examination given them upon the matter contained in the syllabus. This portion of the class was instructed to make a careful study of the whole of Gray's Revised Lessons, and encouraged to collect specimens, study and classify them, and make a herbarium of at least fifty species to in part represent the work done in the field.

Thus in six exercises pupils were more than started in the study of plants, and there is no question that a groundwork was laid for an acquaintance with botany that should be one of constantly growing interest as the years succeed each other.