Edmund Russow an authority on Sphagnaceae (sphagnum mosses) and remembered for his research in plant anatomy and histology, in particular studies of the plant family Marsileaceae (aquatic and semi-aquatic ferns). The plant genus "Russowia" is named in his honor, as is "Sphagnum russowii" (Russow's sphagnum). Edmund Russow Edmund August Friedrich Russow (24 February 1841 – 11 April 1897) was a Baltic German biologist born in Tallinn (), in present-day Estonia. Son of a military engineer, Edmund Russow studied at the Universities of Tartu () and Berlin. In 1867 he became an associate professor at Dorpat, where from 1874 to 1897, he served
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