英国学生科学读本 第75期:蒲公英(3)(在线收听

   Lesson 75 Only A Weed

  第75课 蒲公英
  When the dandelion flowers have all received their supply of pollen, and their seeds are "set" or fully formed,
  当蒲公英的花朵全部获得它们所需的花粉、种子也“做好准备”或者说完全成型之后,
  the yellow flower-heads close up inside their circle of green leaves, and bend down to the ground for a few days while the seeds ripen.
  黄色的头状花序将蜷缩在绿叶的怀抱之中, 在种子成熟的这几天时间里低头向地面弯曲。
  When the heads open and rise up again, a great change is seen to have taken place.
  当头状花序再次打开, 向上伸展时, 它们已经发生了巨大的变化。
  Each dandelion is no longer a golden yellow flower, but a round white ball of down!
  每一支蒲公英都已经不再是金黄色的花朵了, 变成了毛茸茸的白色圆球!
  What can have changed it so?
  如此剧烈的变化是怎么回事呢?
  Let us get one of those white downy balls and see whether we can find out the cause of this change.
  我们摘下一朵这样的白色绒球, 看看能不能解开这种变化背后的成因。
  Pulling off one of the white plumes , and you will find a little round seed-vessel at the end of it.
  摘下一根白色绒毛, 就会发现, 末端有一个细小的球形种皮。
  This long white plume has grown from the white hairy calyx which we found outside each tiny yellow flower.
  这些长长的白色绒毛就是从黄色小花外面的白色毛状花萼中生长而出。
  The yellow parts have all fallen off, for the seed-vessel had no more need of them.
  其中黄色的结构已经全部掉落, 因为种皮完全不需要它们了。
  The first puff of wind that comes breaks off the ripe seed-vessels and their white plumes, and away they go sailing over the fields and the hedges.
  微风吹来, 白色的绒毛从成熟的种皮上脱落下来并随风飘扬, 飞越田间与树丛。
  Did you ever help the dandelion to spread its seeds, by blowing on the ripe head "to see what o'clock it is"?
  你是否曾经拿起过一朵蒲公英, 朝着绒球吹上一口气, “看看它是几点钟”?这其实就是在帮助它们传播种子。
  Children sometimes call these white dandelion heads "clocks, " and try how many puffs of their breath it takes to blow off all the down.
  有时候, 孩子们将这些白色的蒲公英花团称作“时钟”, 然后试着看用几口气才能把所有的绒毛吹下来。
  If it takes four puffs, they say it is "four o'clock.
  如果吹了四下, 那么这团蒲公英就是“四点钟”。
  It is a great advantage to the dandelion flowers to have seeds that are easily blown about by the wind; for if all the seeds fell on the ground close to the parent plant,
  只需一阵微风, 蒲公英花朵上的种子便会随风飘扬, 这可是一种巨大的优势;因为, 如果所有的种子都掉落在亲本株周围的地面上,
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