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staining substances a;ppear outside the nucleus. As in 

 some other cases, the impression is got hère that the 

 formation of the endosperm takes place rather irregularly, 

 as if in various spots within the embryosac pièces of 

 endosperm-tissue would form which grow towards each 

 other so that seemingly more than one endosperm lies 

 in the embryosac. At any rate this seems to be so when 

 one limits his attention to one préparation ; by comparing, 

 however, the différent successive sections of one ovule 

 there finally appears to be only one mass of endosperm. 

 The formation of the endosperm begins in the lining of 

 the wall of the embryosac and from there proceeds in- 

 wardly; in this process the cavity is gradually filled up, 

 the endosperm now meets itself from various sides and 

 it is thèse divisional lines that remain visible. 



That the formation of an endosperm starts indeed at 

 the periphery of the embryosac, appears e.g. from an ovule, 

 collected on September 19 (flg. 8). Hère the size of the 

 whole endosperm is greater than in the already mentioned 

 ovules (diameter 1,35 mm.), so that only a very narrow 

 layer of nucellus tissue is visible ail round, mostly at 

 the chalaza (greatest diameter of the nucellus 1,4 mm.); 

 but the whole endosperm is hollow and in this cavity 

 remuants of the protoplasm of the embryosac are visible. 

 The endosperm-cells are hère of very différent sizes and 

 so also the nuclei vary mueh. Some of them look normal, 

 show karyokinesis, others are enlarged, hâve assumed ail 

 sorts of capricious shapes, the number of nucleoli has 

 greatly increased and a number of fragmentation stages 

 can be observed (flg. 10, 11, 12 and 13). 



Two ovules, collected on September 10, show a still 

 further developed endosperm. The nucellus tissue has been 

 more displaced, the shape of the endosperm-cells is pretty 

 regular, their cell-wall is somewhat thickened, the nuclei 

 are almost normal ; in any case there is much less indication 



