T 











1920] EDWA RDS—HEDYOSMUM 



4*3 



8. Johnson 



Box. Gaz. 



34:321-338. 1902. 



9- , Seed development in the , Piperales, etc. Johns Hopkins Univ. 



Circ. no. 178. 29-32. 1905. 



10 



The 



and extension of sporogenous tissue in the flower of Piper Betel L. var. 

 monoicum CDC. Jour. Exp. Zool. 9:715-739. 1910. 



**. , Studies in the development of the Piperaceae. II. Peperomia 



hispidula. Amer. Jour. Bot. 1:323-339; 357-397. 1914. 



12. Solms, H. A., Chloranthaceae in DC. Prodromus 14:1869. 



13. Van Tieghem, Ph., Traite de Botanique. 1884 (p. 1398). 



EXPLANATION OF PLATES XXXIV-XXXVI 



All figures are camera drawings from microtome sections except figs. 9, 

 10, 24, and 25. Abbreviations used: Ant, antipodals; Br, floral bract; EdN, 

 endosperm nucleus ; Em, embryo; Esp, endosperm; Fl, flower; In, integument; 

 I In, inner integument; MN, male nucleus; MMC, megaspore mother cell; 

 OC, oil containing cell; OIn, outer integument; Osp, oospore; OvC, ovarian 

 cavity; PC, perianth cavity; Pe, perianth; Pi, pits; Po, pore; PT, pollen 

 tube; Sg, synergid ; SyC, sty lar canal; Tp, tapetal cell and tapetum; VB, vas- 

 cular bundle; VB-ov, VB-nc, VB-pe, VB-sy, vascular bundles of ovary, nucellus, 

 perianth, and style; WO, wall of ovary. 



Fig. 1. — Transverse section of stamen showing 3-layered wall, tapetum, 

 and young pollen mother cells; Xno. 



Fig. 2.— Detailed drawing of archesporium of one microsporangium with 

 tapetum, etc., shown in fig. 1; X650. 



Fig. 3. — Tetrad of young pollen grains; X1230. 



Fig. 4. — Transverse section of nearly mature anther; Xno. 



Fig. 5. — Section of mature pollen grain; Xnoo. 



Fig. 6. — Polar view of wall of mature pollen grain; Xnoo. 



Fig. 7. — Longitudinal section of young female flower and bracts; X55- 



Fig. 8. — Similar section of two flowers, upper slightly older than one shown 



^ fig. 7; X55. 



Fig. 9. — Surface view on one side of a young female flower; X55. 



Fig. 10. — Surface view of one side of older female flower; X55- 



Fig. 11. — Transverse section of female inflorescence showing various 



early stages in carpellary development; X50. 



Fig. 12. — Longitudinal section of female inflorescence; X5°- 



Fig. 13. — Similar section of very young flower showing initiation of 



ovarian cavity; X550. 



Fig. 14. — Similar section at later stage showing initiation of style and 



stigma; X250. 



Figs. 15-20. — Successive transverse sections (numbered from base to 

 apex) of single young female flower and subtending bract; X55- 



