Through Magic Glasses and Other Lectures

little world, nor even to one of the widespread oceans which cover so much of it, but to one single pool lying just above the limits of low tide, so that it is only unc

rbed. As it is, however, for many years past I have had only to make sure as to the time of low tide, and put myself in the tr

llecting specimens for our salt-water aquarium. I find now the only way is to lie flat down on the rock, so that my hands and eyes are free to observe and handle, and then, bringing my eye down to the edge of the pool, to lift the seaweeds and let the sunlight enter into the chinks and crannies. In this way I can catch sight of many a small being either on th

as full of living things as the heavens are of stars, and the tide as it comes and goes brings many a mother there to f

at another of baby sea-urchins only visible to the naked eye as minute spots in the water, at another of young jelly-fish growing on their tiny stalks, and splitting off one by one as transparent bells to float away with the rising tide. Or it may be that the whelk has chosen this quiet nook to depo

nd mussels wedged in the cracks. These can be easily seen with the naked eye, but they are not the most numerous inhabitants; for these we must search with a magnifying-glass, which will reveal to us wonderful fairy-forms, delicate crystal vases with tiny creatures in them whose transparent lashes make whirlpools in the water, living crystal bells

g.

aweeds (nat

filicina. 3, Polysiphonia urce

moved only from the aquarium, where I keep it supplied with healthy sea-water, to the tiny transparent trough in which I place it for a few hours to see the changes it has undergone. I could tell yo

g.

d, greatly magnified to show

ores swimming out. h, Holes th

grows in long ribbons in a sunny nook in the water. I have placed under the first microscope a piece of this weed which is just sending out young seaweeds in the shape of tiny cells, with lashes very like those we saw coming from the moss-flower, and I have pressed them in the position in which they would naturally leave the p

nt, and works harder for its living, using the darker rays of sunlight which penetrate into shady parts of the pool. So it comes to pass that its cells divid

g.

63 much magnified to

3, Polysiphonia urceolata

istory of these urns (see No. 3, Fig. 65) is much the same in the two classes of plants, only that instead of the urn being pushed up on a thin stalk as in the

olour, grow upright in stiff groups about three or four inches high; and others, which form crusts over the stones and weeds, are a pale rose colour; but both kinds, when the plant dies, leaving the stony ske

g from them show that they are working up food out of the air in the water, and giving off oxygen. The brown weeds lie chiefly under the shelves of rocks, for they can manage with less su

belong to the same family, and, in fact, if you buy at the seaside a group of seaweeds gummed on paper, you will most likely get both these among

g.

w likeness between the animal Se

icinalis. 2, Ser

it was of no interest. But I have long since given up thinking this of anything, especially in my pool, for my magic glass has taught me that there is not even a living speck which does not open out into something marvellous and beautiful. So I chipped off a small piece of rock and brought the fringe home, and found, when I hung it up in clear sea water as I have done over this glass trough (Fig. 67) and looked

g.

t of rock over a water trough. Also piec

there, the delicate animal-flowers spread out on each side of the stem, and the tree is covered with moving beings. These tentacles are feelers, which lash food into a mouth and stomach in each cup, where it is digested and passed, through a hole in the bottom, along a jelly thread which runs down the stem and joins all the mouths together. In this way the food is distributed all over the tree, which is, in fact, one

, and all the thousands of mouths are spread out in the water. One large form called the sea-fir Sertularia cupressi

for it is so minute and transparent that even when the weed is in a trough a magnifying-glass will scarcely detect it. And I must warn you that if you want to know any of the minute creatures we are studying, you must visit

he vase hc being the horny covering or carapace of the body, which last stands up like a tube in the centre. If you watch carefully, you may even see the minute atoms of food twisting round inside the tube until they are digested, after they have been swept in at the wide open mouth by the whirling lashes. You will se

g.

a and Chilomonas amyg

g. 4, Chilomonas amygdalum. hc, Horny carapac

does. It may serve the animal either for breathing, or as a very simple heart, making the fluids circulate in the tube. The next interesting point about this little being is the way it retreats into its sheltering vase. Even while you are watching, it is quite likely it may all at once draw itself down to the bottom

all, called a Monad (No. 4, Fig. 68). These are so small that 2000 of them would lie side by side in an inch; that is, if you could make them lie at all, for they are the most restless little beings, darting hither and thither, scarcely even halting except to turn back. And yet though there are so many of them, and as

eed, on the tree-like Sertulari? as well as in al

ants, called Diatoms, which live both in salt and fresh water, are single cells feeding and growing just like those we took from the water-butt (Fig. 29, p. 78), only that instead of a soft covering they build up a flinty skeleton. They are so small, that many of them must be magnified to fifty times their real size before you can even see the

g.

g dia

acillaria paradoxa. c, Gomphon

another in a string, but each one of these is a single-celled plant with a jelly cell surroun

g.

iatoma vulg

and d, b, Two flint skeletons formed by new val

and by disappears, leaving only the separate flint skeletons such as you see in Fig. 16. The last form, d, is some

a is larger than the younger one b and fits over it like the cover of a pill-box. As the plant grows, the cell enlarges and forms two more valves, one c fitting into the cover a, so as to make a complete box ac, and a second, d,

e become too small to go on increasing. Then the plant must begin afresh. So the two halves of the last cell open, and throwing out their flinty skeletons, cover themselves with

ons also have survived. The towns of Berlin in Europe and of Richmond in the United States are actually built upon ground called "infusorial earth," composed almost entirely of valves of these minute diatoms which have accumulated to a thickness of more than eighty feet! Those under Berlin are fresh-w

s, and examine them carefully. The first, called the Cydippe, is a lovely, transparent living ball, which I want to explain to you because it is so wondrously beautif

g.

pe Pi

m, Mouth. c, Digestive cavity. s, Sac into which the tentacles are withdrawn. p, Ba

e retreating tide must just have left a shoal behind. Put a tumbler on the desk in front of you, and if the light falls well upon it you will see a transparent ball about the size of a large pea marked with eight brigh

running down the bands. From this cavity the food, which is digested in the stomach, is carried by the canals all over the body. The smaller tubes which branch out of these canals cannot be seen clearly without a very strong lens, and the only other parts you can discern in this transparent ball

colours, till, as it moves more and more rapidly these colours, reflected in the jelly, seem to tinge the whole ball with colours like those on a soap-bubble, while from the two sacs below come forth two long transparent threads like spun glass. At first these appear to be simple threads, but as they gradually open out to about four or five

done by a special apparatus. The cross ridges which we noticed on the bands are really flat comb-like plates (p, Fig. 71), of which there are about twenty or thirty on each band; and these vibrate very rapidly, so that two hundred or more paddles drive the tiny ball through the water.

which acts as a stomach, and many other points in common with the Actinozoa. We cannot help wondering, as the little being glides hither and thither, whether it can see where it is going. It has nerves of a low kind

ey leaf which looks only like a dead dry seaweed; yet you will be wrong, for a more wond

in a glass globe by itself with sea-water, for the little creatures living in this marine city require a very good supply of healthy water and air. I have called it a "marine city," and now I will tell you why. Take the piece in your hand and run your finger gently up and down it; you will glide quite comfortably from the lower to the higher part of the leaf, but when you come back you will feel your finger catch slightly on a rough surface. Your pocket lens will show why this is, for if you

g.

Flustra (Flus

gnified. s, Slit caused by

slit slowly open, and begin to turn as it were inside out, exactly like the finger of a glove, which has been pushed in at the tip, gradually rises up when you put your finger inside it. As this goes on, a bundle of threads appears, at first closed like a bud, but gradually opening out into a crown of tentacles (a, Fig. 72), each one clothed with hairs. Then you will see that the slit was not exactly a slit after all, but the round edge where the sac was pushed in

g.

nimal in the Flu

sheath. s, Slit. t, Tentacles. m, Mouth. th, Throat. st, Stomach. i, I

these under the microscope (see 2, Fig. 73) as the creature lies curiously doubled up in its bed, with its body bent in a loop; the intestine i, out of which the refuse food passes, coming back close up to the slit. When it is at rest, the top of the sac in which

k with these, on the other side, making in all 13,440 alcoves. Now a moderate-sized leaf of flustra measures about three square inches, taking all the rounded lobes into account, so you will see we get 40,320 as a rough estimate of the number of beings on this one leaf. But if you lo

ff from it three to five buds, forming alcoves all round the top and sides of the first one, growing on to it. These again bud out, and you can thus easily understand that, in this way, in time a good-sized leaf is formed. Meanwhile the creatures als

the Sertularia, and count the number of mouths on a branch of my animal fringe (Sertularia tenella); if you make acquaintance with the Thuricolla in its vase, and are fortunate enough to see one divide in two; if you learn to know some of the beautiful f

ctuca, because this species, being composed of only one layer of ce