蜘蛛的品种很多,全世界约有三万多种,在我国至少也有三千种以上。蜘蛛分布很广,森林、田间、草丛、水边、室内都可以看到它们。蜘蛛大小相差悬殊,有的小得像针头,而有的则大得如同手掌。蜘蛛是结网能手,但也有些蜘蛛是不会结网的,会结网的蜘蛛,体内有会分泌胶质液体的丝腺,尾端下部有个结网用的“纺织器”,那些像胶质样的液体经“纺织器”喷出体外就编织成丝网了。发粘的胶质丝一旦和空气接触就会硬化,并带有弹性。那么蜘蛛是怎样结网的呢?它先是像架桥一样,放出一条蜘蛛丝,并固定一端,然后待飘荡的另一端粘着 There are many varieties of spiders, there are about more than thirty thousand species in the world, there are at least more than three thousand in our country. Spiders are widely distributed, forests, fields, grass, water, indoor can see them. Spiders vary in size, some are as small as needles, while others are as big as palms. Spiders are knot nets, but some spiders are spiders that do not knot, knot nets, silk glands that excrete glial fluids, and “knitters” that mesh with the underside of the tail The gum-like liquid is spun out of the body through a “weaver” to be woven into a screen. Sticky gummy filaments harden and contact with air once they are in contact with air. So how is the spider net-forming? It is like a bridge at first, releasing a spider silk, and fixing one end, and then to the other end of the floating adhesion