Is Okumo on the wall poisonous? (common, common)

Introduction to spiders

Arthropoda (Arachnida): The general name for all species of Arachnida (Arachnida or Arachnida). It is distributed all over the world except Antarctica. From sea level to 5000 meters above sea level, it is land. Body length 1 ~ 90 mm, the body is divided into chest (front) and abdomen (back), and the head and chest are covered with carapace and chest plate. There are two pairs of appendages in the head and chest. The first pair is pliers, with a forceps tooth and a poisonous gland opening at the tip of the forceps tooth. The pincers in the orthopalatine suborder move back and forth, and the pincers move laterally in the opposite direction; The second pair is whisker limbs, which are in the form of feet in female spiders and immature male spiders, and are used to hold food and act as sensory organs; However, in the male adult spider, the terminal segment of the whisker limb expands and becomes a connector for transmitting * * * *. Spiders mostly feed on insects, other spiders and multi-legged animals, and some spiders also feed on small animals. Jumping spiders have good eyesight and can dive at close range to catch prey within 30 cm.

2. Morphological characteristics

Spiders vary in length from 0.05 mm to 60 mm. The body is divided into chest and abdomen. Some species have breastplates behind the head and chest (some don't), and there are usually eight in front of the head and chest? Monocular (also 6, 4, 2, 0), arranged in 2 ~ 4 rows. There is a big chest plate on the ventral surface, and a lower lip between the two frontal lobes in front of the chest plate. The abdomen is not segmented, and the abdominal stalk evolved from 1 abdominal segment (the seventh body segment). The abdomen is mostly round or oval, and some have various strange-shaped protrusions. The ventral rotator evolved from appendages, and there are 8 primitive species, which are located slightly in the front; Most six kinds? The rotator is located in front of the rear end of the body; Some species have four spinnerets, and there are many spinning tubes on the spinneret, which are connected with various silk glands, and the silk is spun from the spinning tubes. Sensory organs include eyes, various sensory hairs, auditory hairs, lyre and tarsal bones.

3. Internal structure

The internal structure of spiders is quite special in the book Lung of Respiratory Organs. Inside the lung of a book is a capsule, and the wall of each capsule protrudes inward with many leaf-like folds, just like a page. Spider venom gland is cylindrical, and the gland wall is composed of a layer of cells. There is a catheter in front of the poison gland, which opens near the front end of the claw. Poisonous glands secrete venom, which is lethal to small animals, and some can be life-threatening. For example, if you are bitten by a red spider or a cave tarantula, you must treat it in time to avoid life-threatening.

When it comes to spiders, an ugly image may come to everyone's mind: eight curved and segmented legs, a spherical abdomen, and a pair of jaws with more or less toxins ... This image often makes people who don't know much about spiders think it is a pest.

However, is this the case? I have observed spiders for a while and found that most spiders are not pests, but they are very beneficial to human beings! They caught a large number of pests in their own unique way.

As far as I know, there are two ways to catch insects: the first is the "waiting for the rabbit" method.

It first weaves a gossip-shaped sticky net with silk in its belly, and then hides in a corner that is not easy to be found, waiting for the arrival of flying insects. If some unlucky flying insect hits the net, its body will get stuck and can't move.

At this time, the spider will quickly climb over, bite the prey and inject "anesthetic" into its body to turn the internal organs of the prey into liquid.

And finally? Dinner, of course! I have only seen the second method of catching insects once, and I don't know much about it.

This method of catching insects is relatively simple, and there are not many prey caught: it will pounce on its prey like a beast.

At the speed of spiders, it is ok to catch some reptiles that can't fly, but what about those flying insects? Will greatly reduce the discount! In addition, spiders are also excellent meteorologists.

On a sunny day, it lazily basks in a large horizontal net. Of course, if it can stick to an insect, it will be an unexpected gain for spiders.

On rainy days, spiders will leave the horizontal web and weave a vertical web in another shelter.

When you come back after the rain clears, you will find that the horizontal net has been smashed by raindrops, but the vertical net is intact.

According to this phenomenon, we can know that it will be a sunny day when spiders make horizontal webs; When spiders spin vertical webs, it will rain.

After this introduction, you should know something about spiders! In fact, my observation is only one-sided, and spiders also have pests.

Do you want to know? Please use your head and observe more. If anyone knows more about spiders, please communicate with me to enrich our knowledge.

Observe the composition of spiders. Today I observed spiders carefully.

Today, when I came home from school, I saw something black on the osmanthus tree. When I looked intently, it turned out to be a spider with a big belly and a thin waist. It's weaving a web! The rain just now destroyed the cobwebs.

It is in a hurry to repair it.

What a big spider! About 2 cents in size, with dark brown skin.

Eight claws clung to a chubby belly, which was hanging in the air. Look carefully, there is a silvery white silk thread hanging in the air. The top of the silk sticks to a branch, and the spider's tail follows. As the eight claws kept paddling, the spider silk was continuously elongated.

The spider landed on the stake below to fix the filament.

Quickly return to the original high branches along the trunk.

If he jumps, he won't fall.

At this time, a bird swooped down and broke the net at once, taking away a large piece of net silk.

Okumo looked at the broken net regretfully and darned it calmly.

It seems to knit faster this time! Spiders are small, but their indomitable spirit is worth learning.

Today, I played ball in the yard.

Suddenly, I saw a net with an Okumo on it.

This Okumo is a bit scary-it is as big as a walnut and its legs are three centimeters long, which is longer than its body.

I saw that spider seemed to be sleeping, but when I looked carefully, it was moving, not sleeping.

After a while, it began to walk around on its own internet, as if taking a walk.

I thought it was very interesting, so I caught an ant and threw it on its net.

I saw this Okumo, like a bullet, running to the ant's side in a second.

This Okumo pointed her head at the ant and bit it in half. Then, this Okumo swallowed its food bit by bit.

After eating the delicious food, it stayed on the internet and waited motionless.

Suddenly, another fly flew to its net.

This time, however, Okumo didn't eat the fly like he ate ants last time.

Its hand seems to be spinning around the fly like magic. After a while, the fly turned into a white ball.

Finally, Okumo slowly pulled the fly back to its nest.

I picked up another bug and threw it into the cobweb.

Compared with Okumo, that bug is like a grape and a watermelon. Only the watermelon opened its mouth and swallowed the grapes in one bite.

I went back to my room and looked through the encyclopedia. I found that this kind of spider is called spider. This spider should be a male, because the book says that it is about 20 mm long and its web will be round at dusk, so it is called a spider.

Spider composition Spider 2004 Ruian Daily 65438+February 28th I never liked spiders.

Black body, thin and long legs, and the body is out of proportion, a pair of thieves bright eyes abrupt outside, it is disgusting.

What is even more annoying is spider silk-spiders always weave webs in every corner of the room. I heard that spider silk is poisonous, and once I accidentally let it fly into my eyes when I walked. I can't find it, but it can't be blown out by air. My eyes are red with pain.

So no matter where I find spiders, I will step on them mercilessly, take off my shoes and beat them until they are eliminated.

However, a special experience made me realize that spiders also have a lovely side.

It was summer, and I was doing my homework at my desk in front of the window. I was unhappy because I couldn't solve a difficult problem for a while.

At this time, a heavy rain suddenly came, and the bean-sized rain fell heavily on the window glass, and the rain flowed down the glass.

The air in the room was so dull that I stopped my pen and looked out through the glass window.

Just under the eaves not far from the window, a spider was weaving a web, and the strong wind tore a big hole in the web. Seeing that the spider's hard work was in vain.

I think: this annoying little animal should retreat from difficulties and find a place to hide from the rain.

Unexpectedly, the spider is still trying to repair the cobweb.

It kicked its legs hard, wiped off the rain, redrawn the gaps broken by the wind, and opened a decent net.

The strong wind is blowing again, and the newly woven net is broken again, which is even worse this time.

I snickered, thinking that it would give up this net and turn away after the pain.

However, after it straightened up, it began to mend and persevere, still fighting for its goal.

The scene in front of me reminds me of a touching story.

/kloc-At the beginning of the 0/9th century, a British general was defeated on the battlefield, fled everywhere, and hid in the haystack of the farmhouse to avoid the wind and rain. He was miserable and depressed.

At a loss, he suddenly found a spider trying to spin a web in the corner. The spider silk was blown off again and again, but the spider was not discouraged and finally ended the web.

The general was greatly encouraged, then rallied and finally defeated his opponent Napoleon at the Battle of Waterloo.

This general is the famous Wellington in history.

Outside the window, the rain is still falling and the wind is still blowing, but I firmly believe that this spider will finally achieve its goal-weaving a complete web.

After this incident, I no longer hate spiders. Although it is so ugly and disgusting, I can feel that there is a spirit in it called "never give up", which is exactly what I need.

E-mail: 325204 Pan Lingling (Comment), Class 5 (2), No.4 Primary School, Tangxia Town, Ruian City, Zhejiang Province, has a novel selection of materials, which is a major feature of this composition.

The author is good at grasping every bit of life and describing his psychological process from hating spiders to not hating them, which gives people a refreshing feeling.

The content of the article is concrete and vivid.

Observing the spider mending the web in a thunderstorm can clearly write the spider's every move and the mood changes during the observation, and can also quote a short story to make the lyrics at the end come naturally.

(recommended by teacher Lin Bingcheng) Tel: 13 157793459

I wrote a composition about spiders last night and found a fat Mi Chong crawling on the dining table.

I asked my father, "Can you feed this fat Mi Chong to the little spider?" Dad said, "Of course.

"So, under the pressure of my father and I, this Mi Chong crustily skin of head landed on the spider web.

To my great surprise, the little spider did not bravely rush to catch its prey, but ran away.

Is the little spider afraid of the fat man? My dad and I stood there 1 minute.

And the white and fat guy found himself cheated and struggled desperately to quit.

The spider's web has broken a hole, and it is about to succeed. Just then, the little spider ran out quickly and wrapped it tightly with silk. Mi Chong only showed his head, and he couldn't escape anyway.

So, a big meal of fat worms began. ...

When it comes to spiders, an ugly image may come to everyone's mind: eight curved and segmented legs, a spherical abdomen, and a pair of jaws with more or less toxins ... This image often makes people who don't know much about spiders think it is a pest.

However, is this the case? I have observed spiders for a while and found that most spiders are not pests, but they are very beneficial to human beings! They caught a large number of pests in their own unique way.

As far as I know, there are two ways to catch insects: the first is the "waiting for the rabbit" method.

It first weaves a gossip-shaped sticky net with silk in its belly, and then hides in a corner that is not easy to be found, waiting for the arrival of flying insects. If some unlucky flying insect hits the net, its body will get stuck and can't move.

At this time, the spider will quickly climb over, bite the prey and inject "anesthetic" into its body to turn the internal organs of the prey into liquid.

And finally? Dinner, of course! I have only seen the second method of catching insects once, and I don't know much about it.

This method of catching insects is relatively simple, and there are not many prey caught: it will pounce on its prey like a beast.

At the speed of spiders, it is ok to catch some reptiles that can't fly, but what about those flying insects? Will greatly reduce the discount! In addition, spiders are also excellent meteorologists.

On a sunny day, it lazily basks in a large horizontal net. Of course, if it can stick to an insect, it will be an unexpected gain for spiders.

On rainy days, spiders will leave the horizontal web and weave a vertical web in another shelter.

When you come back after the rain clears, you will find that the horizontal net has been smashed by raindrops, but the vertical net is intact.

According to this phenomenon, we can know that it will be a sunny day when spiders make horizontal webs; When spiders spin vertical webs, it will rain.

After this introduction, you should know something about spiders! In fact, my observation is only one-sided, and spiders also have pests.

Do you want to know? Please use your head and observe more. If anyone knows more about spiders, please communicate with me to enrich our knowledge. ....

I found spider eggs. I found spider eggs. I like observing nature since I was a child. Everything about nature fascinates me and intoxicates me.

Immersed in the pleasure of observation for countless times.

I am often ecstatic about my unexpected discoveries.

I remember an autumn a few years ago, when I was idle, I went into the grass in front of my house alone to catch cricket.

I was trying to catch it when suddenly an Okumo appeared in front of me.

I looked at this Okumo carefully.

I found a little thing like a bubble ball behind this Okumo.

I thought: What is this? What is a spider doing with a foam ball on its back? What's the use? ..... all the questions are bothering me, which makes me want to know what it is.

So, I carefully took the ball off the spider.

I held it tightly in my hand and ran upstairs quickly, ready to open the ball and see what was inside.

So, I took out two small clips, carefully clamped the two sides of the ball, tore it hard, tore off the skin and rolled out a lot of yellow transparent balls.

I thought: What is this? Why is this ball wrapped in such a small yellow ball? I didn't know what it was, so I put it on my desk and read it carefully.

After a while, I suddenly thought of looking at it with a magnifying glass.

So, I took out a magnifying glass, put the little yellow ball in a bright place and observed it with a magnifying glass.

I watched carefully and suddenly saw a little spider wrapped in these balls.

I took a closer look, and it turned out that the yellow skin was the body of the little spider inside.

After seeing these, I couldn't help crying out with joy, "I found spider eggs …" Through this incident, I understood that every discovery in the world came from his careful observation at ordinary times. Only in this way can you have a comprehensive understanding of nature and enrich your knowledge.

You can make continuous progress and development.

Tutor: Jiang Yaling

How do spiders prey on insects? Long Tianci, Class 6, Xiutian Primary School, Nanning (1) Abstract: How do spiders prey on insects? Looking at this Okumo, it suddenly occurred to me that spiders are not experts in catching insects. How does it eat insects? National Day is coming. One day, I passed the corner and saw many vegetables beside it. Between a vegetable and a small tree, I found an Okum sitting motionless on its net.

This spider is different from the one at home. It has a big belly with many white and green patterns on it. You can tell it's toxic at first sight.

The web it weaves is thicker than ordinary spiders, especially the one with two intersecting webs in the middle.

Looking at this Okumo, I suddenly thought: Aren't spiders experts in catching insects? How does it catch insects? So, I took a small bottle to catch bugs in the vegetable field.

There are many insects in the vegetable field. If you are careful, you can catch a lot.

What bugs are we going to catch? Catch the grasshopper. Grasshoppers have muscular thighs and great strength when bouncing. It can jump far, maybe it can break through the spider web.

After a while, I caught two grasshoppers. They're not hurt. They're strong. I put them in front of cobwebs and call them traps.

Sure enough, as I expected, they couldn't see the spider web, so they jumped on it together and got stuck.

The two grasshoppers didn't struggle on the spider web, and the spider didn't eat them at once. I guess, because grasshoppers don't move, spiders can't feel their existence.

Then, the grasshopper may think there is no danger and struggle. At this time, Okumo quickly ran to the grasshopper and tore off the net around him. The grasshopper was caught in a net. Although it is strong, it can't move any more.

Sure enough, the spider feels whether there is prey through vibration, but the spider does not eat the grasshopper and returns to the middle of the net. Instead, it slowly spits out silk, then sticks it next to the hole, constantly changes its position, constantly spits out silk, and finally makes up the silk.

At this time, another grasshopper struggled, and the spider broke a hole in the old way, but patiently repaired it. Isn't this perseverance and hard work of spiders worth learning? I decided to catch another grasshopper and feed it to Okumo, but this time the result surprised me. I didn't expect this grasshopper to be so lucky. It jumped to the edge of the spider's web and the spider didn't notice it. And it ran away.

After this experiment, I gained a lot. I not only learned the spirit of spiders, but also knew that the captured prey may not have no way to escape, and there is still a chance to survive. Most importantly, I know how spiders catch insects.

The spider composition of the insect crab spider Although the striped spider we mentioned earlier works very hard, it has been tirelessly building a comfortable nest for its eggs.

But in the end, it can no longer take care of its home.

Why? Because its life is too short.

When the first cold current comes, it will die.

Its eggs will not hatch until winter.

It had to leave its nest.

If the baby can be born when the mother is still alive, I believe that the spider mother will take care of the little spider like a bird.

Another kind of spider proved my guess; It is a spider that can't weave a web: it just waits for its prey to run close to it, and it walks sideways, a bit like a crab, so it is called a crab spider.

This spider can't use a web to find food. Its hunting method is: ambush behind the flowers and wait for the prey to pass by, then go up and gently stab its neck. Don't underestimate this gentle thorn, it can kill prey.

The crab spiders I have observed especially like to hunt bees.

Bees are so focused on collecting nectar that they won't consider abandoning it.

It licks nectar with its tongue, then chooses a stamen that can collect a lot of nectar and begins to work wholeheartedly.

While it is working hard, the crab spider has been waiting to sneak out of its hiding place, walk behind the bee, get closer and closer, and then rush up and stab it at a certain point behind the bee's neck.

No matter how hard the bees struggle, they can't get rid of the sting.

This stab is not a random blow.

It just stung the nerve center of the bee's neck.

The nerve center of the bee was paralyzed, and the legs began to harden and could not move.

One second, a little life came to an end.

The killer crab spider sucked its blood happily and contentedly, wiped its mouth after sucking it, and cruelly threw its remains aside.

However, we will see that this cruel executioner is a very kind and gentle mother at home.

Just like that "cannibal", although he eats other people's children mercilessly, he loves his own children very much.

We are the same under the pressure of hunger. People and animals are cannibals.

Although the crab spider is a killer who kills bees without seeing blood, you have to admit that it is also a very beautiful little thing.

Although their bodies are not very good, like a short and fat cone carved on a stone foundation, and there is a small piece of bulging meat on one side, like camel bees, their skin is better than any satin, some are ivory and some are lemons.

Some of them are particularly beautiful: pink rings on the legs, crimson patterns on the back, and sometimes a light green belt on the left or right side of the chest. Although this dress is not as rich as the striped spider, it looks more elegant and noble than the striped spider's dress because of its less flabby belly, meticulous pattern, bright color and harmonious collocation.

People stay away from other kinds of spiders, but they should not be afraid of beautiful crab spiders, because they are so beautiful and lovely. If it is a small thing that can't be moved, everyone will definitely put it down.

Crab spider's nest in nesting, crab spider's superb skills are no less than its foraging skills.

I once found it in a water wax tree, when it was nesting among a bunch of flowers. It is knitting a white silk bag shaped like a thimble: this white silk bag is the nest of its eggs, and the mouth of the bag is covered with a round and flat fluffy cover.

At the top of the roof, there is a dome made of wool with some withered petals. This is its observation deck.

From the outside to the observation deck, there is an opening as a passage.

On this observation deck, the crab spider is like a conscientious guard who stays here every day.

Since laying eggs, it has lost a lot of weight than before, and almost completely lost its youthful appearance. It is absorbed in this watchtower. When there is any trouble, it will be nervous all over, bury its head in a state of readiness, and then come out from there, waving a leg to intimidate its uninvited guests. It gestured excitedly to tell it to leave here, otherwise it would be at its own risk.

Its ferocious appearance and exciting action really scared those malicious or innocent outsiders, and only after driving away those sneaky guys did it return to its post with satisfaction.

So what does it do under the dome made of silk and petals? It turned out that it was stretching to cover up its precious eggs.

Although it is very thin at this time, it seems that a gust of wind can take it away, but it has forgotten its own diet. In order to watch its work, it has now given up sleep, stopped catching bees and sucking their blood to satisfy its hunger, and just sat quietly on its eggs.

I can't help thinking of hens.

The same is true of hens hatching eggs. The difference is that the hen's body can provide heat. When it hatches an egg, its warm air is transmitted to the egg, awakening the seeds of life.

The heat provided by the sun is enough for spiders.

Mother spider no longer needs to provide heat.

In fact, it has no ability to provide heat energy.

Because of this difference, we can't call the waiting of spiders "hatching the next generation".

After two or three weeks, the female spider became thinner and thinner because she didn't eat anything.

But its watch work has not slackened at all.

What does it want before it dies? It seems to have been waiting for something, what makes it difficult to support itself and support its lifeless body with its spirit.

What is it waiting for? What is worth waiting so hard for with its life? Later, I learned that it was waiting for its children to come out, and the dying mother could do something for them.

The striped spider's children are orphans before leaving the balloon-shaped nest. No one came to help them break the nest, and they were unable to break out of it themselves. Only when the nest breaks open automatically can they send the little spider to all directions.

They didn't even know who their mother was when they came out.

The crab spider's nest is tightly closed, so it won't automatically crack and the top cover won't automatically rise. So how did the little spider come out? When spiders hatch, we will find a small hole on the edge of the lid.

This hole didn't exist in the past, ...

Today, in the morning reading class, everyone was studying hard, and suddenly I don't know who called out, "Look! A spider! On the blackboard! " The students were attracted at once, and all stopped, looking at spiders and talking about spiders. No one was in the mood to study.

At this time, Teacher Zhang stood by the door and said, "Students, everyone usually says it is difficult to keep a diary. I don't know what to write. Now's the chance.

Please observe the spider beside the blackboard carefully, see what it looks like, and think about why it came to our classroom. What do you know about spiders? Write when you go back, it will be a good diary! "So I carefully observed this naughty spider.

I found it has eight legs. When climbing, the front two legs move first, and the back six legs follow.

It has a small spherical body with a big mouth in front.

It must like mosquitoes very much.

But why did it come to our classroom? Some students said: "it must be afraid of the sun, so come to our classroom to hide."

Some students said, "no, it must come to our classroom to learn knowledge!" "... what a lovely spider this is! It makes our morning reading class so interesting! ...

Please indicate the source? Is Okumo on the wall poisonous? (common, common)