The brook runs below. Alders and ash, bending forward on either bank, mingle their branches and form a verdant arch. At their feet, behind a porch of great twisted roots, are watery caverns prolonged by gloomy corridors. On the threshold of these fastnesses shimmers a glint of sunshine, cut into ovals by the leafy sieve above.

This is the haunt of the red-necktied minnows. Come along very gently, lie flat on the ground and look. What pretty little fish they are, with their scarlet throats! Clustering side by side, with their heads turned against the stream, they puff their cheeks out and in, rinsing their mouths incessantly. To keep their stationary position in the running water, they need naught but a slight quiver of their tail and of the fin on their back. A leaf falls from the tree. Whoosh! The whole troop has disappeared.

On the other side of the brook is a spinney of beeches, with smooth, straight trunks, like pillars. In their majestic, shady branches sit chattering crows, drawing from their wings old feathers replaced by new. The ground is padded with moss. At one's first step on the downy carpet, the eye is caught by a mushroom, not yet full-spread and looking like an egg dropped there by some vagrant hen. It is the first that I have picked, the first that have I turned round and round in my fingers, inquiring into its structure with that vague curiosity which is the first awakening of observation.

Soon, I find others, differing in size, shape and color. It is a real treat for my prentice eyes. Some are fashioned like bells, like extinguishers, like cups; some are drawn out into spindles, hollowed into funnels, rounded into hemispheres. I come upon some that are broken and are weeping milky tears; I step on some that, instantly, become tinged with blue; I see some big ones that are crumbling into rot and swarming with worms. Others, shaped like pears, are dry and open at the top with a round hole, a sort of chimney whence a whiff of smoke escapes when I prod their under side with my finger. These are the most curious. I fill my pockets with them to make them smoke at my leisure, until I exhaust the contents, which are at last reduced to a kind of tinder.

What fun I had in that delightful spinney! I returned to it many a time after my first find; and here, in the company of the crows, I received my first lessons in mushroom lore. My harvests, I need hardly say, were not admitted to the house. The mushroom, or the bouturel, as we called it, had a bad reputation for poisoning people. That was enough to make mother banish it from the family table. I could scarcely understand how the bouturel, so attractive in appearance, came to be so wicked; however, I accepted the experience of my elders; and no disaster ever ensued from my rash friendship with the poisoner.

As my visits to the beech clump were repeated, I managed to divide my finds into three categories. In the first, which was the most numerous, the mushroom was furnished underneath with little radiating leaves. In the second, the lower surface was lined with a thick pad pricked with hardly visible holes. In the third, it bristled with tiny spots similar to the papillae on a cat's tongue. The need of some order to assist the memory made me invent a classification for myself.

Very much later there fell into my hands certain small books from which I learnt that my three categories were well known; they even had Latin names, which fact was far from displeasing to me. Ennobled by Latin which provided me with my first exercises and translations, glorified by the ancient language which the rector used in saying his mass, the mushroom rose in my esteem. To deserve so learned an appellation, it must possess a genuine importance.

The same books told me the name of the one that had amused me so much with its smoking chimney. It is called the puffball in English, but its French name is the vesse-de-loup. I disliked the expression, which to my mind smacked of bad company. Next to it was a more decent denomination: Lycoperdon; but this was only so in appearance, for Greek roots sooner or later taught me that Lycoperdon means vesse-de-loup and nothing else. The history of plants abounds in terms which it is not always desirable to translate. Bequeathed to us by earlier ages less reticent than ours, botany has often retained the brutal frankness of words that set propriety at defiance.

How far off are those blessed times when my childish curiosity sought solitary exercise in making itself acquainted with the mushroom! 'Eheu! Fugaces labuntur anni!' said Horace. Ah, yes, the years glide fleeting by, especially when they are nearing their end! They were the merry brook that dallies among the willows on imperceptible slopes; today, they are the torrent swirling a thousand straws along, as it rushes towards the abyss. Fleeting though they be, let us make the most of them. At nightfall, the woodcutter hastens to bind his last fagots. Even so, in my declining days, I, a humble woodcutter in the forest of science, make haste to put my bundle of sticks in order. 'What will remain of my researches on the subject of instinct? Not much, apparently; at most, one or two windows opened on a world that has not yet been explored with all the attention which it deserves.

A worse destiny awaits the mushrooms, which were my botanical joys from my earliest youth. I have never ceased to keep up my acquaintance with them. To this day, for the mere pleasure of renewing it, I go, with a halting step, to visit them on fine autumn afternoons. I still love to see the fat heads of the boletes, the tops of the agarics and the coral-red tufts of the clavaria emerge above the carpet pink with heather.