<Tr> <Td> Bryophyta </Td> <Td> mosses </Td> <Td> 12,000 </Td> </Tr> <Tr> <Td> Pteridophytes </Td> <Td> Lycopodiophyta </Td> <Td> club mosses </Td> <Td> 1,200 </Td> <Td> 12,000 <P> (12,200) </P> </Td> </Tr> <P> (12,200) </P> <Tr> <Td> Pteridophyta </Td> <Td> ferns, whisk ferns & horsetails </Td> <Td> 11,000 </Td> </Tr>

Who classified plants on the basis of their water requirements