Opuntia ficus-indica Opuntia ficus-indica Opuntia ficus-indica (prickly pear) is a species of cactus that has long been a domesticated crop plant grown in agricultural economies throughout arid and semiarid parts of the world. Likely having origin in Mexico, "O. ficus-indica" is the most widespread and most commercially important cactus. Common English names for the plant and its fruit are Indian fig opuntia, Barbary fig, cactus pear, and spineless cactus, among many. In Mexican Spanish, the plant is called nopal, while the fruit is called tuna, names that may be used in American English as culinary terms. Fig opuntia is grown primarily as
What Is and What Should Never Be descending riff [of "What Is and What Should Never Be"] is amazing: It's like a bow is being drawn back, and then it releases. The rhythm of the vocals is almost like a rap. It's insane — one of their most psychedelic songs." This was also one of the first songs recorded by the band for which Robert Plant received writing credit. According to rock journalist Stephen Davis, the author of the Led Zeppelin biography "Hammer of the Gods: The Led Zeppelin Saga", the lyrics for this song reflect a romance Plant had with his wife's younger sister. "What Is