RESERVE CELLULOSE. 27 



4. The cells of the endosperm, near the chalaza, are the first to have their walls 

 thickened; those next the integuments are next aifected; and the cells near the embryo 

 are the last to mature. 



5. In some seeds (Iris) reserve cellulose in its 3-ounger stages has the property 

 of swelling; with water, and goinsT- over into a inucilairinous modification. This swellintr 

 is noticeable in the mature seed, after long continued boiling in water. 



The reserve cellulose of Paris and Trillium seeds swells with water before maturity. 

 This is true of Paris, when the seed is ripe, and will, undoubtedly, prove true of Trillium 

 also. 



6. With the exception of Paris and Trillium the association of starch with reserve 

 cellulose has not been observed as a reserve constituent of the cell in seeds of Liliaceae. 



In Colchicum, starch is found outside the endosperm in the crest of the I'ipeniiig 

 seed. 



In Galanthus, Scilla, Lloydia, and Narcissus it is found in the endosperm cells during 

 the later stages of the ripening of the seed, perhaps a sign of arre-*t in processes of 

 development. When the seed is fully matured the starch is not present. 



In Convallaria, Fritillaria, Tofieldia, Anthericum, and Asphodelus it is never present 

 in the seed. 



In Asparagus and Polygonatum, starch-builders, with minute grains of starch, are 

 found in certain cells of the endosperm before the thickening of the wall begins ; during 

 the processes of thickening, they are not visible. 



In Iris a little starch appears in the cells of the chalaza, never in the endosperm, 

 before any tliickening takes place. 



EXPLANATION OF THE I'LATES. 

 The ilriiwiiigs are made with the camera hicida, where not otherwise specitied. 



PLATE 1. 



Fig. L Cells from the ripe endosperm of the seed of Polj/gonatuiti multijlorum ; from material preserved in abso- 

 lute alcohol. X 350. 



Fig. 2. Cells from the endosperm of Iris pseudacorus ; firm, dry seed, treated with iodine, x 050. 



Fig. .3. Cells from the dry seed of Ornithoijnlum caudatum ; contents removed by chloral hydrate, x •'550. 



Fig. 4. Cells from the endosperm of Gidtimiii riindicnns ; contents removed by chloral hydrate, x .'350. 



Fig. 6. Cells from the endosperm of Ilosta caerulea ; oil aggregated with treatment with chloral hydrate, x 350. 



Fig. 6. Cells from the endosperm of TuHpa yesneriana ; from the dry seed ; treated with iodine, x 350. 



Fig. 7. Cells from the same, in section transverse to the long axis of the cells ; from the dry seed, treated wilh 

 iodine, x 30. 



Fig. 8. Cell from the endosperm of Paris quadrifolia ; almost ripe; with absolute alcohol and iodine: a, nucleus; 

 6, starch grains ; c, oil drops, x 350. 



Fig. 0. Cells from the endosperm of Puris quitdrifolia ; .showing reserve material of the walls swollen with treatment 

 with water. The seed is of the same age as in Fig. 8, not (luite ripe; a, nucleas ; h, starch grains; c, oil drops, x 350. 



