*Hansraj College, University of Delhi.
Botany Department, University of Delhi, Delhi
A comparative anatomical account of the stem and leaves of the diploids and colchicine induced tetraploids of lberis amarL. and Linaria maroccana has been presented. The increased thickness of tetraploid leaves in Iberis as well as Linaria was found to be due to an increase in cell size and not to an increase in cell number. Further, tetraploidy in Iberis was accompanied with an increase in size of chloroplasts. This was, however, not true for Linaria where the size of chloroplasts was the same in 2n and 4n leaves.
There was an increase in the number of cells in cortex and pith of the 4n,stems of Iberis amara L. This was, however not the case in Linaria where the number of cells in cortex and pith was almost the same in the 2nd and 4th stems. A slight general increment in the size of cells in teiraploid stems was noted.
