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EXPLANATION OF PLATE X 
(Unless otherwise stated, the figures are from Zamia.) 
Fic. 1. Diagram of the crown; a, peduncle of ovulate strobilus of last year; 
b, young ovulate strobilus; v, position of the vegetative point. X1 
Fic. 2. Longitudinal section of two ovulate strobili; between horn is the 
vegetative point (v) and the leaves (/) surrounding it; the upper portion of the 
strobilus is cut away. X1 
Fic. 3. Longitudinal section of ovulate strobilus; v, vegetative point; J, 
rudimentary leaves; two vascular bundles enter the strobilus. 23. 
Fic. 4. Longitudinal section of staminate cone (June 14); v, vegetative 
point; /, rudimentary leaves. X23. 
Fic. 5. Longitudinal section of three staminate strobili (July 15); v, vegeta- 
tive point; youngest strobilus (st) is cut at an angle. X11. 
. 6. Diagrams: a, sympodium; 6, sympodium with shortened internodes; 
6, Beocaicdeaes with internodes shortened until strobili are on a level, as in Zamia. 
Fic. 7. Longitudinal section of young staminate strobilus (June 1), showing 
primordia of sporophylls (sp) and leaves surrounding strobilus. X27. 
Fic. 8. Longitudinal section of typical vegetative point and rudimentary 
leaves. X 32. 
IG. 9. Lnipiriediaat section of staminate strobilus (July 8), showing sporo- ~ 
phylls. x23. ; 
Fic. 10. Longitudinal section of staminate strobilus a little further advanced 
than in fig. 7. X32 
