398 Cooke and Schively on Observations on the 
EXPLANATION OF PLATES. 
Pirate XXIX. 
Epiphegus Virginiana, parasitically attached to root of American Beech. 
Chasmogamic and cleistogamic flowers are both developed on this 
specimen. 
PLATE XXX. 
Fig. 1. T. S. of tuber, showing endogenously developing root. 350°. 
Fig. 2. T. S. of Beech root spreading into the looser tissues of the 
parasite. XX 350°. 
Fig. 3. L. S. of chasmogamic flower of Epiphegus, showing calyx, 
corolla, one of the four stamens and pistil. >< 75°. 
Fig. 4. L. S. of cleistogamic flower. XX 75°. 
Fig. 5. T. S. of ovary from cleistogamic flower, with large nectary, 
composed of richly protoplasmic cells, cut in section. > 350°. 
Fig. 6. Young ovule or macrosorus, enclosing a large developing 
macrospore cell. > 350°. 
PLATE XXXI. 
Fig. 7. L. S. of developing macrospore cell, surrounded by [tapetal (?) 
and] sporangial tissue. > 350°. 
Fig. 8. L. S. of developing macrospore cell, later stage, showing con- 
stricted protoplasm of the macrospore cavity, with two nuclei at 
either end. 
Fig. 9. L. S. of micropylar end of macrospore or embryo-sac cell, 
showing two spindle figures at right angles to each other. XX 350°. 
Fig. 10. Innermost layer of macrosporangial cells, surrounding syner- 
gids and egg, large vacuolated endosperm cell with two fusing 
nuclei, also three antipodal cells. 350°. 
Fig. 11. L. S. of young ovule or macrosorus. The two endosperm 
nuclei have here fused. 200°. 
Fig. 12. L. S. of upper part of macrospore cavity, filled with endo- 
sperm cells that enclose a divided egg-cell. > 350°. 
Fig. 13. Later stage than last, showing surrounding endosperm cells, 
tip of a pollen tube, suspensor cell and embryo cell with two 
nuclei. XX 350°. 
Fig. 14. Second division proceeding in embryo-cell. 350°. 
Fig. 15. Four-celled stage of embryo. X 350°. 
PLaTE XXXII. 
Fig. 16. L. S. of sixteen-celled stage of embryo and suspensor. Eight 
of the sixteen cells and the four suspensor cells are seen in sec- 
tion. XX 350°. 
Figs. 17a-k. Stages in development of the microspores. 350°. 
