Page:Popular Science Monthly Volume 33.djvu/389

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BOTANY AS IT MAY BE TAUGHT.
375

black mustard, 16,416; and burdock, 36,456. The plants chosen were all average ones. A "Flora of a Stubbie-Field" was that of a few acres where oats had grown. The Compositæ and Gramineæ orders were represented by the largest number of species, and furnished by far the greatest percentage of specimens. Two species of rag-weed and the foxtail grass covered four fifths of the field. However, thirty-five species in sixteen orders were represented. Many of these matured their seeds before September 17th, and nearly all before October 10th. Leaves of young, rapidly growing shoots were compared with those of slow-growing branches of old trees, and gave a good idea of the variability of foliage within the same species, or even the same shrub or tree. "Unequal-lobed Leaves" furnished a topic for the study of seeming irregularity, which is, however, a comparatively constant peculiarity in some species. The time of "Opening and Closing of Flowers"; "Dispersion of Seeds, a Comparative Study of Two Labiate Flowers"; "Five Largest Wild Flowers," "Are our Weeds mostly Annuals?" "Anatomy of the Milkweed (Aslepias) Flower," and "Sensitive Stamens of Purslane," are other topics studied by the class, the results of which were none the less interesting because the length of this paper forbids particular mention of each.

To hold each student to an examination upon the work of all these topics of research was not feasible, therefore the notes taken by each member of the class upon the reports of all others were inspected. This secured a record for each student of all the important features brought out under the topics of research, and also furnished a basis for a class-mark as required by college law.

The closing exercise of the term was upon anatomy. A brief outline of the work done in the laboratory is given below. In way of preface it should be said that the students were entirely unacquainted with the compound microscope at the beginning of the term. The first day was spent in learning how to manipulate the instrument, cut thin sections, etc. The brittle stems of the common purslane are excellent for beginners to practice upon with the razor or scalpel. For the second day pollen of several kinds was studied, and ovaries in transverse and longitudinal sections. Accurate drawings are required of all prescribed work. The flower of the large thistle (Cnicus altissimus) filled the third afternoon. On the fourth day the stem of richweed (Pilea pumila) was studied. This subject is highly recommended to all instructors in vegetable anatomy who have not tried it. The course of each bundle is clearly seen from the outside of the comparatively transparent succulent stem. The duckweed (Lemna) is excellent for small roots and prominent root-caps, and the hairs of the squash illustrate living cells, with nucleus, nucleolus, and circulation of protoplasm. Following these, a comparative study was