\'1I. Hxi'LAXATION OF PlATES 



PLATE 7 



Stem-biuls of TriUinm .<.<'.s.s/7r var. (jif/anteum from the rootstock crown in 

 various stages of development. iSemi-diagrammatic. 



Fig. 1. Longitudinal section of bud collected in November, primordia not 

 all present, still very rudimentary, fifteen months before its active season above 

 ground commences. 



Figs. 2 and 5. Bud in February: figure 5, entire, figure 2 in longitudinal 

 section. Primordia more highly differentiated than in November. The sepals 

 slightly surpass the foliage leaves. 



Figs. 3 and 6. Bud collected in May: figure 6 entire and figure 3 in longi- 

 tudinal section. The foliage leaves are seen to be shorter than the sepals. 

 Sepals and petals now include the stamens and carpels. At about this time the 

 archesporial cells are cut off in the young anthers. 



Figs. 4 and 7. Bud as it w^ould appear late in July: figure 7 eutire and 

 figure 4 in longitudinal section. The foliage leaves are now" growing rapidly 

 and equal or slightly surpass the sepals in size. As in figure 3, the maturing 

 anthers practically fill the interior of the fiower bud. In T. ovatum the flower 

 bud at this season would be elevated in a short peduncle. For comparative 

 sizes of the different parts of the stem-buds in September, see figure 1, page 44, 

 h,, b, . 



Fig. 8. Portion of cross-section of a young anther showing archesporial 

 cells just cut off. Collected May 29, 1915. 



Fig. 9. Portion of young ovule showing the niegaspore mother-cell. Col- 

 lected October 7, 1914. 



Fig. 10. First division of megaspore mother-cell. Collected February 26, 

 1915. 



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