The Book of Pilgrimage (Kitab Al-Hajj)
Muslim :: Book 7 : Hadith 2717
A'isha, the wife of the Apostle of Allah (may peace be upon him). said: I heard Allah's Messenger (may peace be upon him) as saying: Four are the vicious (birds, beasts and reptiles) which should be killed in the state of Ihram or otherwise: kite (and vulture), crow, rat, and the voracious dog I (one of the narrators, 'Ubaid- ullah b. Miqsam) said to Qasim (the other narrator who beard it from 'A'isha): What about the snake? lie said: Let it be killed with disgrace.