124 BOTANICAL GAZETTE [AUGUST — 
PLATE III, 
Fic. 1. Vertical section of young flower bud. x 30. 
Fic. 2. Transverse section of young flower bud of same age asin fig. 1; dotted — 
outline represents position of carpel tips in higher sections. X 30. 
1G. 3. Vertical section of older flower bud. X 30. 
Fic. 4. Transverse section of young stamen. X 232. 
Fic. 5. Transverse section of single microsporangium of older stamen. X232. 
Fic. 6, Tranverse section of portion of microsporangium and wall in micro- 
ae ae cell stage. > 400. 
G. 7. Transverse section of portion of microsporangium and wall with 
Paes mother cells in synapsis. 232. 
Fic. 8. Transverse section of mircosporangium and portion of wall; pollen 
mother cells in mitosis. 400. 
Fic. 9. Pollen mother cells in metaphase of first mitosis. > 400. 
Fic. 10. Tetrads of ot xX 400 
Fic. 11. Pollen . 400. 
Fic. 12. Pollen eas after division of nucleus. x 400. 
Fic. 13. Transverse section of mature seo X 20. 
Fic. 14. Transverse section of young ovary. 
Fic. 15. Transverse section through middle fs ae mature ovary. %7- 
7. Trans 
Fic. 18. Longitudinal section of ovule with megaspore mother cell and integ- 
ument. 232. 5 
Fic. 19. Transverse section of single lateral placental outgrowth, showing 
difference in rate of development of integument on different parts of the placenta; 
somewhat diagrammatic. > 40. 
PLATE IV. 
Fic. 20. First maturation division of megaspore mother cell. > 400 
Fic Linear series of three megaspores, arising by failure of nical 
daughter cell to divide. x 400. 
22. Tetrad of megaspores in which the micropylar daughter cell has 
Fic 
divided longitudinally. 400 
Fic. 23. Longitudinal section of ovule, with tetrad of eticuede chalazal 
one enlarging and encroaching on single layer of nucellus. x1 
Fic. 24. Longitudinal section of portion of ovule showing le embry? 
sac, nucellus, and columnar tissue. X 232. 
Fic. 25. Longitudinal section of portion of ovule showing four-celled embry° 
SAC. XxX 232. 
Fic. 26. Longitudinal section of portion of ovule showing fully developed 
embryo sac. 
FIG. 27. Lomsindian section of portion of ovule — embryo sac after 
fusion of polar nuclei; antipodals pushed to one side. 232 
