Why does the spider family bear the name Archnida?

Ages ago, people believed there was magic in the weaving of a spider’s web and the Greeks told a story about a girl, Arachne, who was to give all spiders the name of Arachnida.

One day, Archne, who was skilled in the art of weaving, challenged the goddess to a contest. She proved herself better than Athene at the craft and that immortal goddess, jealous and enraged that a mere mortal should defeat her, changed Archne into a spider, eternally doomed to weave her web with the thread spun from her own body.

It is interesting to see how scientists have classified animals in order to bring out their natural evolutionary relationship. There are other creatures in the class of Archinda, including scorpions, mites and king-crabs. Arachnida is grouped under Arthropoda, the class of animals with an outer skeleton made of chitin-a horny substance, the body divided into segments with jointed limbs. Arthropoda in turn comes under Metozoa-animals with bodies made up of many cells. Metozoa is one of the two main groupings of animals, the other is Protozoa which consists of very small, usually microscopic, animals found in fresh water or in the sea and having only one cell.