thought proper of his material in the preparation of an inexpensive book, designed to teach the Elements of Botany on Professor Henslow's plan of selected Types, and by the use of "Schedules."

Feeling that there might be good service in a book of this kind, which, instead of interfering with the excellent text-books of Botany already published, might serve rather as introductory to them, and suffice, with constant reference to the plants themselves, to insure to the diligent learner a sound foundation for more advanced Botanical studies, I determined to prepare these "Lessons in Elementary Botany," basing the systematic portion (Part II.) upon the Type Lessons, which formed the largest and most valuable part of Professor Henslow's manuscripts.

As no sufficient introduction to Systematic Botany had been prepared by Professor Henslow, I have drawn up a few chapters, embracing the elements of Structural and Physiological Botany, treated in as simple a way as appeared to me consistent with practical usefulness. These elementary chapters it is desirable beginners should master before undertaking the methodical study of the Ordinal Types. In working up the latter, I have made the most free use of Professor Henslow's materials, frequently quoting entire passages from his manuscript. I have, however, omitted much which Professor Henslow

had introduced, with a view to show the important "instructional value" of Botany as an 66 educational weapon," in the opportunity which Botanical Lessons afford the teacher of introducing to his class a large amount of useful information upon topics of the most varied kind. Thus I find a lesson in pneumatics apropos of pop-guns made of the stem of the Elder; an account of soap-making, and the method of ascertaining specific gravities, in connexion with the Olive order, represented in Britain by the Ash; how to analyse a Potato, under the Bittersweets; an account of wonderful bells, under the Bellflowers; of glass-making, under the Saltworts, formerly burnt for the sake of their alkaline salts; of brewing, under Hops; and the like. I have omitted such matter because it would require more space than could be afforded in a book of small cost, to be used by private learners as well as by teachers; and also because the variety of topics which a teacher may thus introduce, and which his own intelligence may suggest, is infinite.

Professor Henslow's plan of employing "schedules," designed to direct the attention of the pupii at once to the most important points of structure, I have adopted in my own class with much advantage. Their use should be commenced as soon as the first six chapters are thoroughly acquired. Any printer would strike off a few hundred blank

"schedules at a small cost, but the necessary form may be easily drawn with pen or pencil by the student himself. I strongly recommend their use, both by private students and in colleges and schools.

Most of the excellent woodcuts employed in this work were drawn by Professor Henslow's daughter, Mrs. Barnard, of Cheltenham, from the admirable Sheet Diagrams designed by Professor Henslow, and executed by Mr. Fitch, for the Committee of Council on Education. They have been liberally placed at the disposal of the publishers by the Rev. George Henslow.

KEW, September 1868.

D. O.

In the present edition I have been allowed to make some little alterations, chiefly in the chapter on minute structure and vital processes. To students trained in the newer school of Botany, these must, no doubt, seem inadequate, but regarding this as a First Book, specially intended for use in schools and for young people taking up Botany remote from class-room and laboratory, I think it better not to alter materially the relative proportions hitherto assigned in it to the different sections of general morphology, anatomy, function and classificatory

matter.

KEW, November 1885.

D. O.

LESSONS IN BOTANY.

PART I.

CHAPTER I.

A BUTTERCUP IS EXAMINED.

1. The Root. Its form and general structure it penetrates the soil; is colourless; irregularly branched; destitute of leaves; and its extremities are sheathed.

2. The Stem.-It ascends; is coloured; bears leaves and branches at definite points: the extremities are not sheathed, but give off, successively, rudiments of leaves. 3. Foliage-leaves.-They are borne by the stem only. "Radi

cal" and "cauline" leaves: thin, coloured green, consisting of an horizontally expanded blade with, or without, a petiole.

4. Flowers consist of leaves.

The peduncle. Suppression of internodes in flowers. The receptacle of the flower.

5. The sepals; forming the calyx.

6. The petals; forming the corolla.

7. The stamens; bearing anthers which contain pollen-grains. The stamens are hypogynous.

8. The carpels; each containing an ovule. The stigma. The style. The carpels, collectively, constitute an apocarpous pistil.

9. The carpels persist after the other parts of the flower fall away. The fruit; seed; embryo and albumen.

10. A summary of the parts examined.

GA

'ATHER, first of all, a specimen of the Common Buttercup.

There are at least three different plants included under this name, almost equally common in meadows and pastures over all England, and most of Scotland, but as

O. B.

B

they nearly resemble each other it does not signify which is taken. In gathering the specimen take it up carefully, so that the root may be uninjured.

Proceed now to examine your buttercup.

1. Observe the ROOT, noting in what respects it differs from the parts which grow above ground. It consists of numerous fibres, about the thickness of small whip-cord, tapering at their extremities and giving off irregularly

sh

FIG.

·r f..

section through the ex

many thread-like fibrils. It is destitute of the green colouring of the stem and foliage, being pale or nearly white it bears neither buds nor leaves, and its branches, from their direction, appear to have avoided the light.

If you can find the tip of one of the root-fibres uninjured, cut it off, and examine it minutely with your magnifying glass. In case you have not the means of examining it with a higher magnifier, you will find figure I a sufficiently correct representation of it, divided through the 1.- Longitudinal middle and magnified many times. tremity of a root-fibre The point which I want you particuof Buttercup, mag- larly to note is this. The extremity nified. g growing of the fibre is covered by a closely fitting sheath, protecting the actual growing point, which is hidden immediately within the end of the sheath, to which it is directly joined. This protecting sheath is being constantly renewed, at its inner side, by the growing point," so that as the outer layers become worn or withered, by forcing a way through the soil and pebbles, they are constantly replaced by inner layers which take their turn, replace them, and then die; to be in like manner replaced by fresh inner layers derived from the "growing point," so long as the root continues to live.

root-fibre.

66

The "growing point," as I call it, you perceive consists of a group of minute thin-walled cells with opaque contents, the arrangement of which in relation to each other, or indeed to the surrounding tissues, can hardly be