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W. C. TWISS 
Plate XXXIV 
Fig. II. Cell from periphery of young disc of Preissia. Benda's method (unbleached). 
Large bodies with dark borders, violet; smaller, uniformly-colored structures, brown. 
X 1800. 
Fig. 12. Cell from same region, showing only larger bodies. X 1800. 
Fig. 13. Portion of older disc, showing development of plastids, with large grains of 
storage starch. Iodine stain, with Benda's fixation. X 800. 
Fig. 14. Two cells from central part of same disc, showing fully developed grains. 
X 800. 
Fig. 15. Series of developing starch grains, from near the periphery of the disc to its 
center. X 900. (Fig. 15 on Plate XXXIII.) 
Fig. 16. Cell from thallus of Preissia. Benda's method (unbleached). Large 
" chloro-leucoplasts " light blue, with dark violet peripheries and filled with starch grains. 
Smaller bodies, dark brown. X 900. 
