1. Structure of plastids was investigated using variegated plants of 41 species belonging to 22 families. For the study of plastid development, Agave americana var, variegata Nichols and a variegated form ofAllium fistulosum L. were employed. The results were summarized in Table 1 and Figs. 1 and 2. 2. Albicated plastids account for the structural abortion. The number of grana in albicated plastids is remarkably small in comparison with that of the normal green chloroplasts. Accordingly, albicated plastids are usually devoid of chlorophyll. 3. InAgave andAllium, the granum in albicated plastid ceased to multiply at an earlier stage of development. 4. Molisch's reaction is found to be positive in all albicated plastids as well as in normal green chloroplasts, 5. In some species of Liliaceae, albicated plastids and green chloroplasts were present admixed in a single cell.