PLATE IX. 
Fig. 1 . Young flower in which the pistil is not completely formed. 
Fig. 2 Very young pistil showing budding of nucellus, n 
Fig. 3. Y'oung ovule with an archisporialcell (a), and showing origin of 
the integuments (b), dermatogen of nucellus d. 
Figs. 4-5. r l here are two archisporial cells, a. 
Fig. 6 Four archisporial cells, a; shows also decreased amount of nucel- 
lar tissue, nt, and integuments, b. 
PLATE X. 
Fig. 7. The lower archisporium («) developing into macrospore at the 
expense of the other three cells, a v 
Fig. 8 . The macrospore ( a ) has attained nearly its full size, and only 
rudiments of the other three cells are present, a v 
Fig. 9. A two-celled embryo sac, a. 
Fig. 10. A four-celled embryo sac {a), the tip of which is now in close 
relationship to dermatogen, d. 
Fig 11 . An eight celled embryospsac ( a ), but only two cells of egg appa- 
ratus ( e ) are shown. Three antipodal cells {at), polar nuclei which have not 
yet united, pn. 
Fig. 12. The same as 11, but a little later stage, polar nuclei pn, in 
process of fusion. 
Fig. 13. Mature embryo sac ready for fertilization. Egg apparatus e, 
definutive nucleus dn, antipodals at. 
Fig. 14. Egg cell undergoing process of fertilization. Egg nucleus en, 
pollen nucleus pn , pollen tube pt. 
Fig. 15. Fertilized egg e\ endorsperm nucleus end. 
Fig. 16. Egg cell e , endosperm, end. 
PLATE XI. 
Fig. 17. Suspensor 5 , embryo em , endosperm, end. 
Fig. 17|. Suspensor s, embryo em. 
Fig. 18. Same os 17£, slightly older. 
Fig. 19. Embryo and endosperm a , embryo enlarged, b. 
Fig. 20 . Nucellus, auc; integments, it, Micropyle, m; Embryosac, em; 
funiculus, f. 
