In Astrology, Mercury rules the intellect and the way people think.  It blesses Gemini with a quick mind and curses them with sensitive nerves.

Mutable, air sign, masculine.

Gemini governs the press, the internet, fax machines, telephones, newspapers, television and radio. 

Gemini's are represented in the insect kingdom by the Butterfly.  They flutter about gathering tidbits of information, and sampling experiences.