and Fertilization in Oenothera. 
317 
Fig. 1. Mature pollen grain containing degenerated vegetative nucleus ( v .) in centre and 
elliptical generative one (^.) lying in peripheral portion. Plasma is impregnated with immense 
numbers of hyaline fusiform starch grains. 
Fig. 2. Pollen-tube in stylar conducting tissue, showing disorganized vegetative nucleus (z/.), two 
male nuclei ( m.n .) in telophase with plasma sheath, and migrating starch grains. 
Fig. 3. The same, showing a disintegrating vegetative nucleus ( v .). 
Figs. 4-6. Tips of pollen-tubes just lying upon embryo sacs, each of them containing two male 
nuclei embedded in plasma sheath, no vegetative nucleus. 
Fig. 7. The same, typical lenticular male cell is shown. 
Fig. 8. Two tubes {p.) on the sac, one of which made the way between two filiform apparatus 
(yf/.). Apical end of the tube is closed by mucilaginous substance {m.s.). Synergids (syn. x ) are 
filled with starch grains which originated in the pollen grain. 
Fig. 9. a, b. Two successive sections of an egg apparatus cut longitudinally; a is to overlap b in 
the actual state of affairs. Upper synergid {syn.P) has been attacked by tube (/.), contents com¬ 
mencing to flow out over oosphere ( e.c .) through rents ( r ., r., r.). 
Fig. 10. Upper part of embryo sac with six endosperm nuclei, two of which ( e.n .) are shown 
in both sides of egg-cell {e.c.). 
Fig. 11. Egg apparatus with two synergids attacked {syn. x ) by tube (/.). 
Fig. 12. The same, but one synergid attacked. 
Fig. 13. Oosphere cut slantingly at the lower end; two male nuclei {m.n.) enclosed in plasma 
sheaths {p.s.) lying in plasma flow poured out from synergid. 
Fig. 14. Two male cells {m.n. and p.s.) in plasma flow ( p.f. ), through the upper one of which 
egg nucleus {e.n.) is visible. 
Fig. 15. Two male nuclei {m.n.) are just in contact with female elements {e.n.,p.n.). 
Fig. 16. Plasma flow upon oosphere. One male cell is shown. 
Fig. 17. Tube end bursting, starch grains flowing into synergid. 
Fig. 18. Two branchlets of pollen-tube grasping tip of synergid, filiform apparatus {fil.) turned 
over, portion of mixed plasma contents flowing over the latter. 
