Opuntia pailana Opuntia pailana Opuntia pailana is a species of the genus "Opuntia" in the family Cactaceae. The name "pailana" comes from the sierra de la Paila in the state of Coahuila Mexico where it was discovered. The first description was published by Wilhelm Weingart in 1929 in the book "Monatsschrift der Deutschen Kakteen-Gesellschaft". Band 1, Nummer 9, 1929, S. 167–169. As most of the species of the genus Opuntia, "Opuntia pailana" is a shruby plant with cladodes (leaves racket-shaped) up to one meter high. The cladods are in color blue-green or when getting older green-yellow, 10 to 14 centimeters long and
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