Branches of an alder tree hang over the ditch, then its ripe, black plugs are also gladly used as building material. The shapes in the middle of the big picture are common; those with live snails and those on the right with freshwater mussels often together in the same ditch; the phryganids on the left of the drawing are not very common and those drawn farthest to the bottom right are also rare, at least in our country: they occur mostly in fast-flowing streams, their houses are wholly or partly glued together from heavier sand grains; they would therefore always be carried along with the current without that ballast.
Once a tube larvae house was sent to me, which looked remarkably like a snail house.
A naturalist from Tennessee in North America, who first found those empty houses, is having a lot of troubledone, to find also its snail, until it[ 100 ]at last it turned out that he was dealing with an artifice of a caddis damsel; he discovered that the house was built from grains of sand, and later found houses with the larvae in them.
In order to obtain a large number of tube larvae, it is best to keep the net flat on the bottom in a clear ditch and to pick it up every time something comes up above the opening that resembles a phryganide, or anything at all. which has a motion which does not correspond to the flow of water, if there is any current. Though it may seem to you a barren leaf, a bit of bitten reed—if it has a movement of its own, there is life in it.
Towards the evening of warm days the tube larvae usually crawl up on aquatic plants, to eat or to fix up their house. As far as they can, they reach out with the body from the tube; that is often their destruction, for among those fine leaves of hornwort or yarrow lies the enemy lurking. Usually it is a thorn, a beetle or dragonfly larva, which relieves them of further concerns for existence, but…. if you have already acquired some practice in peering through the ditch water, then you may discover something new at the same time.
Take a good look; that white one, there close to the surface. Like a ball of mercury, isn't it? There's another one, and another a little further on; what a big one! This one looks like a silver hazelnut, and the other one over there is a table bell or a glass clock.
It is also a clock, but of a special kind: it is a real diving bell. And the diver is a spider.
Left: A female of the great salamander attaching her eggs to an aquatic plant. Right: a young male showing off.
Left: A female of the great salamander attaching her eggs to an aquatic plant. Right: a young male showing off.
Ha, there you have him already, he has noticed a feeding tube larva. The spider with its silver abdomen waits for a moment for the phryganide to approach. No, it goes the other way. Then let's go! With a few jumps[ 103 ]the water-spider reaches the larva, and ere it perceives trouble, it is seized and has taken a bite; the spider puts all its eight legs on the edge of the opening of the house, a few good jerks with its jaws and... the larva is out, the empty house rises quickly upwards.
The spider with its prey too: it will soon eat its tasty snack on the surface. But just there comes a ridged one, who notices something and turns his head. "That's not good," thinks the spider, "you take care of yourself when you're hungry." He dives into hiding with his sweetie and looks for his bouncy castle in the water again; with his loot he disappears in his silver clock.
If you take the plant out of the water with that silver cup, you will find nothing of it but a bundle of gray silk; the great spider, if it has not escaped under the hand, does not appear to be of silver; its abdomen is downy hairy and mouse-grey. It was a real castle in the air.
If you bring the spider into the aquarium, it will instantly be the beautiful animal again. Very soon he begins to spin a thin web in the water, removes some air bubbles from the surface and rebuilds his airy home; with a few wires it prevents the air mass from rising again. If there is not much in the net or in the air trap itself in the aquarium, it will soon start hunting.
Sometimes this spider manages in a strange way; If you notice in your aquarium a large, apparently empty snail shell that floats with the tip upwards through the water, or rocks to and fro on the bottom, then you can be sure that our water spider has made his home there.
When winter approaches, it usually seeks out such a large snail, eats enough, then also appropriates the house, insures itself against burglary by spinning a dense web in front of the opening and thus sleeps off the harsh winter time.[ 104 ]
In the spring and sometimes again in the autumn, he makes a side room at his air-dwelling house, in which he shelters his eggs; you may notice, if you happen to have a male in the aquarium too—they are much larger, just the other way around as with the land spiders—that two, sometimes three air bells are connected to each other by covered air passages.
But, attracted by that vain silver sheen, we would completely forget that we were collecting damselflies.
In the summer, or if it has been a nice spring, already in the last of May or the beginning of June, you will find few phryganids at the bottom, then the larvae have already pupated again. The opening of their house is closed with an airy woven net (this closure is clearly visible on the top of most tubes) and now you have a much better chance of obtaining the houses by examining the surface of the ditch carefully. to subject.
They now float with the weak current, or hang in stagnant water among floating aquatic plants. Pay attention to everything you see and do not immediately recognize.
There is already some driving; get in guys! Just a flat stick! And that thing over there? Just wait, it floats here; that looks like a miniature rat with a big tail. Would that also be tube larvae?
Look, they're both moving; although there are now also mobile pupae among the insects, the houses of the tube larvae are not alive themselves. So these are not phryganides. Then what?
Larvae of Salamanders and Frogs.
Larvae of Salamanders and Frogs.
1. Salamander in an egg, 10 days after laying. (Increases).
2. Newly hatched salamanders, hanging from a leaf.
2 a Ditto, enlarged .
3. Salamander larva with forelimbs. (Nat. gr.)
4. Ditto, already with four legs. (Nat. gr.)
Tadpoles, Bullheads or Bullheads. On the back, the belly and from the side; the two left 6 weeks, one right 4 weeks old. (To items from an aquarium).
Tadpoles, Bullheads or Bullheads. On the back, the belly and from the side; the two left 6 weeks, one right 4 weeks old. (To items from an aquarium).
Yea, what shall I say, the Latin names sound so learned; we boys simply call them "firecrackers and sticks"; and those two queer little creatures were ahead of them at the time[ 107 ]us the most mysterious creatures that existed. We had some suspicion that they were larvae of some aquatic animal, but all our careful efforts to extract the whole animal from the larvae were always unsuccessful; the firecrackers, as well as the sticks, died or mysteriously disappeared, without a beetle ever appearing in the water; yes, which freaked us out even more, with no doll skin ever to be found anywhere.
Gunfly (stick) Stratiomys chamaeleon. larva; doll opened; people insect.
Gunfly (stick) Stratiomys chamaeleon. larva; doll opened; people insect.
People whom we thought ought to know, and whom we asked about it, called us a Latin name; but it was half forgotten five minutes later, and we couldn't care less for the name alone; we desire to know more about it.
It remained with that desire, at least with me, until I was no longer in school for a long time; until only once, by chance, by meeting a schoolmate from that time or by studying in thick[ 108 ]books, was reminded of the pleasant years when we bartered in all kinds of naturalies, where a "firecracker" had the value of a completely intact pitch-black and the "stick" was never less than a rare phryganide.
On a warm summer's day you must notice how many and how different insects refresh themselves at the open table, which the large umbellifers set out for their welcome guests.
Top left. Gliding on a umbellifer. Under a firecracker (Eristalis tenax) in water, a creeping specimen and a doll sleeve. A hovering fly.
Top left. Gliding on a umbellifer. Under a firecracker (Eristalis tenax) in water, a creeping specimen and a doll sleeve. A hovering fly.
The four-winged bumblebees and bees seldom visit them, their long trunks make it easier for them to draw honey from deep cup- or bell-shaped flowers; for two-winged insects, however, with their short snout, the open umbel is a paradise.
Do you see on that flower that big, beautiful bee in his black and yellow suit?[ 109 ]
Get him! wrong, huh? No, a hoverfly is not so easily caught. Look, there he stands still in the air, his wings are in such a rapid movement that they can hardly be seen; it is as if the creature hangs in the air with its legs down by an invisible thread—there it shoots like an arrow from its bow, straight at the flower from which you have just chased it away. He is in the butterfly net, feel free to take him out with your fingers; it looks like a dangerous bee, and he makes use of that resemblance, but it isn't one; behold, the beautiful creature has but two wings, and such insects have no stinger.
There's another hoverfly there, it's drawn differently and not so hairy; his chest is streaked with gold yellow along the length, his abdomen is also provided with such stripes, but transversely. Also a beautiful animal, isn't it?
Well, those two beautiful hoverflies and other species, which sometimes live far from the ditch between greenery and flowers, were gray, long-tailed firecrackers last week.
That firecracker has crawled up the side of the ditch with little legs that you may not have even noticed yet—a long way into the meadow, or up the dyke slope. There the long tail shrivelled, with which it drew air from the surface in the water; and in its place appeared a pair of ears, which did the same service in the air. Thus the soft, dirty firecracker lay there for a day or so, as grey-brown as the earth among the grass, unseen and unharmed. Then suddenly the tip broke off, and a graceful, miraculous hoverfly saw the light of day. In about fourteen days he will return, “si Dieu lui prête vie” from the flowers to the ditch, to lay eggs on some aquatic plant.
And that stick? If you look closely at the drawing on page 107 ,[ 110 ]you already know a large part of his life history. It is also the larva of a fly (but not a hoverfly) that carries us in our minds from the ditch to the flowery meadow or dike verge.
This fly has a particularly flat, steel-blue or bronze-coloured abdomen, on which a yellow or reddish drawing occurs, which in a few species resembles a coat of arms with diamonds or crossbars. They are also called gun flies. In the middle of the drawing you see the larva before it became a stick; he is just drawing air from his tail tuft for the journey to the bottom; when he goes into hiding later, he takes a good-sized bell with him between the inwardly curved fringes.
When grown up, he uses those two horny hooks on his head to creep up the side and farther into the pasture; sometimes these larvae also pupate in the water, such a pupa is just like a gray piece of wood. But stiff as such a thing may seem, it can still move fairly quickly over the water with S-shaped swings, until it has reached the shore to rest there. You can see what is in such a stick on the left of the drawing, under the fly.
Yes, now we have become acquainted with firecrackers and with sticks, but we have not found any pupa damselflies. That happens more often, for the lover of nature always follows finding, but what he finds is by no means always what he was looking for.
There was a good reason for this: the phryganids rarely occur in the ditches in which firecrackers float; these animals prefer muddy ditches without many aquatic plants, located close to houses, just like their namesakes, the real water rotten.
Two water spiders with nests, attached to (right) Yarrow, (left) Waterweed, in the middle Floating Fountainwort.
Two water spiders with nests, attached to (right) Yarrow, (left) Waterweed, in the middle Floating Fountainwort.
Let's rather search that other ditch: it's a lot[ 113 ]brighter. There are already some floating there; take them home and look every day if you see any butterfly-like, brown, and white spotted animals on the stone in your glass container or on the rock in the aquarium; those are the hatched damselflies. Such butterflies, also known as sedges or sedges, sometimes fly by the thousands towards evening through the tall grass near the water.
Tube damselflies.—Completely removed insects and larva from the tube.
Tube damselflies.—Completely removed insects and larva from the tube.
If you want it, it won't take you much effort to see such a tube lady from the side of the ditch, who has just come out sitting on his floating house; it thus awaits the unfolding and drying of the wings; if the animal dares to fly too early, it falls into the water and flounders, fluttering in fear.
And there is reason enough for that fear; that big frog will go for it; his great stupid, bulging eyes stare at the strange thing for a while, ere he can decide to snap,—there it will come:—[ 112 ]too late, a bugger and a skater, each on one side, have taken hold of the unfortunate damsel, and run away with it; the skater won't let go, he drags the beetle with him; there a swallow skims over the surface of the water: the caddis damsel and the skater vanish together in one wide mouth. The turret has quickly submerged just in time, and it is not for nothing that it has four eyes, two of which look up into the air and two look down into the water.
You should keep some skaters and turrets in your aquarium, that will give a lot of life to the surface. You must not take the skaters with you in a bottle of water, but in a box, otherwise they will have drowned before you come home.
Shaking the bottle makes them submerge, and they can't stand it; they are designed to run fast on the water, but getting in is their death. One can be seen on page 41 .
The turning towers can withstand underwater; as well as on the surface; under the magnifying glass you can find one of the causes of their astonishing swiftness: their middle and hind legs are almost entirely finned.
In case you want to build a collection of water beetles, or if you want to know the exact name of a prisoner, you need a much more extensive work than this booklet; then you must determine; the message is to look closely and compare; especially the number of claws on the last tars indicates a difference in species.
Now it will sometimes happen to you, just like me, that you are very sympathetically warned not to put your mouth above the ditch, because the gases that rise from it can harm your health. it's okay[ 115 ]It is possible that this is a poison just like coffee, but a very slow one.
Probably no one has ever sat with his nose above ditch water more than our old acquaintance Antony van Leeuwenhoek, who turned ninety-one.
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