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about five-eighths of an inch in length, turn his foot to most excellent account. We had pulled the youngster's beard off, and then had deposited him at the bottom of a deep aquarium. The water was probably but poorly aerated, hence he was evidently ill at ease, and to our astonishment he at once began travelling over the pebbly bottom, then up the glass side with the utmost facility and grace. The foot moved precisely as any univalve gasteropod would do, and with the same easy gliding motion. The movement was continued without interruption until it had reached the surface of the water, a distance of not less than ten inches, which added to the distance travelled over the bottom, was probably equal to fourteen inches. At the surface it lost no time in spinning its byssus, which it fixed to the side for a permanent abode.

For its lively colors, perhaps rather ruthlessly, we had picked this little fellow out of a large family cluster, snugly packed in a hole in one of the piles of the dock. It was a large group of all sizes, literally bound together by the silken cords of-attachment shall we say?

A fellow captive was a full grown, black, edible mussel, torn from its anchorage, a stone near by, at low tide. We afterwards found ensconced in this black shell, an amount of intelligence, which filled us with astonishment. If his youthful fellow prisoner could beat him at walking, he was about to accomplish the feat of climbing to the same position by means of a species of engineering of a very high order.

In order the better to understand this singular feat, let us introduce it by the narration of some spider tactics we once witnessed. The insect had captured a large beetle, but could not get it to its web, and seemed indisposed to prey upon it away from its den. from its den. It had dragged the It had dragged the prey under the web, which was about two feet above. It ran up to a

point close by its web; there it attached a thread, by which it speedily descended, and then attached the other end to its

booty. Again it ascended, affixed another thread, then descended and affixed to the prey as before. Each thread, in sailor phrase, was made taut. After a good many threads had been in this manner attached, each being stretched tightly, and each pulling a little, the weight was seen to ascend a small fraction of an inch. Again the threads were increased, and again the weight ascended a little more, until at last, after incredible labor, perseverance and skill, the little engineer had the satisfaction of success; for its well earned booty, with one final, tiny jerk "brought up" at the desired spot. The explanation of all this is simple. Suppose we take a cord of the material known by the ladies under the name elastic, and attach it to an ounce weight. If but very moderately stretched it would certainly pull at least a grain. Supposing it to do that, a second one would pull with equal force, and it would be but a simple estimate to determine how many threads would be required to raise the entire weight. But enough of this. Now for the mussel.

Placed at the bottom of the aquarium, where it had been for a couple of days, it had succeeded in wiggling itself up to one of the glass sides of the tank. This accomplished it protruded its large foot, stretching it up as high on the glass as it could reach, this organ seemingly adhering very tightly. A little hole opened near the extreme forward end. of the foot. This tiny hole was really the extremity of a folded or closed groove. Out of this a drop of white gluten, or mucus, not larger than the head of a pin, was exuded, and pressed against the glass. There was then a slight withdrawing of the foot, simultaneously with an unfolding, or opening of the groove, which contained, as if moulded there, the already completed delicate thread. This done, the partly contracted foot (not drawn into its shell at all, be it understood) was again extended, this time a little higher than before. The groove, or spinneret, was again closed, except the little opening on the surface of the foot, whence another little drop of mucus appeared, which also

was pressed against the glass. Again the foot was withdrawn a little, the lips of the groove unfolded, and the moulded thread set free. This gave thread number two. Each was evidently set at a considerable tension. And in this wise, thread after thread was formed and set. I regret that I did not record the exact number, but am sure that it was about twelve or sixteen, and the time occupied was between two and three hours, when lo! up went the mussel, about three-eighths of an inch high. Yes, he was drawn up by his own cords. He was literally lifted from terra firma. Not at all suspecting what was to follow I mentally exclaimed. "This little fellow knows the ropes."

There was next a period of rest. Whether it was due to exhaustion of material, and was meant to allow the secreting gland time to evolve a fresh supply or not, I cannot affirm; but must say that such was my belief, for after an hour or so it set to work again, precisely as before, attaching a new cluster of threads. This cluster was set about five-eighths of an inch higher than the previous one. When this new group of filaments was finished, the same result followed, another lift of a fraction of an inch, but not quite so high as the first. I now suspected its motive-the animal was actually in this singular manner attempting to reach the surface. It wanted to take an airing, and was really in a fair way to bring it about.

While setting its third cluster of threads, I foresaw a serious difficulty in the way, and one against which the spider never has to contend. It was this: after the third lift had been achieved the threads which had accomplished the first lift had changed direction; that is, the ends of the threads, which had pointed downward when pulling up the mussel, were now pointing upward, and were actually pulling it down. Of course the lowermost thread, or threads, would exert the most retrograde traction. Thought I, "Sir Musselman, you will have to exercise your wits now." I rejoice to say that the ingenious little engineer was complete master

of the situation. The difficulty was overcome in this way -as each lowest thread became taut in an adverse direction, it was snapped off at the end attached to the animal. This, as I think, was done by two processes; the one by softening that end of the thread by the animal's own juices, purposely applied, as the pupa in the cocoon moistens its silk envelope, when wishing to soften the fibres, so that it can break a hole through which the imago may emerge; the other by a moderate upward pulling, thus breaking the filament at its weakest point.

The next day our little engineer had accomplished the wonderful feat of climbing to the surface by ropes, fabricated during the ascent. Without delay it moored itself securely by a cluster of silken lines at the boundary where sky and water met, and was there allowed to enjoy the airing it had so deservingly won. Bravo! my little Mussel-man! No acrobat can beat thee on the ropes!

And what are we to say to all this? Blind instinct, forsooth! Who believes it? The wise men of the ages have written as the tradition of the elders-"byssus-bound," of our Mytilus. But it can make of its bonds, mooring lines of safety against the storm, and with consummate skill can build a silken stair-way into its own wished for elysium of delight. It is some three years since the writer witnessed the facts here recorded, and to this day, the sight of a mussel inspires him with profound reflection on the ways of Him who made these creeping things of the sea.

NOTE. It has seemed to the writer, that in the perfection of movement shown by the Modiola plicatula, as given above, a high stage of foot development is indicated, such as would hint at a grade out-ranking Mytilus edulis. The figure inserted is that of M. edulis; but the process of climbing is the same. - S. L.

FLOWERLESS PLANTS.

BY DR. A. KELLOGG.

THE great coal measures of our continent are the grand storehouses of preserved plants from this richest realm of the vegetable kingdom; they are the entombed pioneers that have paved the way, and still light the path of higher forms of life, both vegetable and animal. However much we may to-day value these humble and lower steps on the stage of existence, we are apt to fall far below a due appreciation of their value in the economy of nature; our health, wealth, comfort, nay our very existence more or less, directly depends on the uses they subserve; and still every new dawn brings some novel use crowding the advancing ages until we look back but a few days to our early years, and wonder how we, as well as our forefathers could do without this or that necessary of life. As coal they are the familiar friends of our labors, and the cheerful companions of the domestic fireside. It is not, however, to the dead and fossilized forms alone, but mainly to the living, that we invite a moment's attention.

An idea of minuteness and insignificance too often follows any reference to the simplest plants in nature; yet many attain a great size, such as Tree Ferns and certain Sea-weeds

-the former forty feet high, of the size of one's body, and the latter of prodigious length, besides myriads of intermediate forms.

The Fungi, a brief account of which follows, are cellular plants, without flowers, living in the air, often nourished through a stem by an amorphous spawn, or mycelium, instead of a root, and propagated by very minute spores, serving the same purpose as the seeds of flowering plants.

The largest species found in California, is the kind commonly known as Touchwood, or Hard Tinder (Polyporus) ; of a semicircular shape, between one and two feet across, (337)

AMER. NATURALIST, VOL. IV.

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