Asplenium rhizophyllum one collection on sandstone in the Shawnee Hills of Illinois. A triploid hybrid between walking fern and Tutwiler's spleenwort was accidentally produced in culture. A similar plant collected from limestone in Shepherdstown, West Virginia could have originated from the same parents, from an unreduced (diploid) gametophyte of Scott's spleenwort crossed with walking fern, or from an unreduced walking fern gametophyte crossed with ebony spleenwort. In 1813, Henry Muhlenberg listed lobed spleenwort as "Asplenium rhizophyllum" var. "pinnatifidum", although he did not provide a description distinguishing the variety from the typical species. It was described as the species "A. pinnatifidum" by Thomas
Leningrad Nuclear Power Plant Leningrad Nuclear Power Plant Leningrad Nuclear Power Plant ( ()) is a nuclear power plant located in the town of Sosnovy Bor in Russia's Leningrad Oblast, on the southern shore of the Gulf of Finland, some to the west of the city centre of Saint Petersburg. It consists of four nuclear reactors of the RBMK-1000 type. These reactors are similar to reactors No. 1 and 2 of the Chernobyl Nuclear Power Plant. Two units of the VVER-1200 type are under construction at Power Plant II to replace the current RBMK reactors when they reach the end of their service lives.