42 



STARCH-GRAINS 



the Pea or Bean, lies in the centre {centric type, Fig. 20, /and 

 g), and the laj'ers are arranged symmetrically aroimd it. The 

 dry grains of Pea, Bean, etc., exhibit a number of radiating 



Fig. 20. — Starch-grains, a-c, stages in tlic development of grains within 

 the chloroplastsof Pf//(o;n'ii; chloroplasts shown blaclc. c]i., cliloroplasts ; 

 5, starch-grains ; d and e, Potato starcli ; / and g. Pea starch ; 

 h, compound starch-grain ot Rice. 



cracks, which appear as dark irregular lines (Fig. 20, ff) ; these 

 seem to be due to the drying up of some of the imbibed water 

 which permeates the substance of all starch-grains. 



