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EXPLANATION OF THE FIGURES. 



Fig. 1. The embryo of Tacca involucrata attached by a funiculus to the albumen. 



Fig. 2. A longitudinal section of the ovary of Hernandia sonora, showing that the tube of the calyx is completely adherent to it; — the involucre is seen surrounding the lower part of the ovary. A small canal which is 



sometimes pervious, is seen extending from the base of the style to the cavity of the ovary. 

 Fig. 3. The ovule of the same, showing the apex of the secundine protruding through the foramen of the primine. 



Fig 4. A stamen of a Hernandia before the dehiscence of the anther. The anther valves are quite smooth; the connective is distinguished from them by being hairy in its lower part, and impunctate with points like very 



short hairs towards the apex. 

 Fig. 5. A stamen of Hernandia sonora after the dehiscence of the anther. 



Fig. 6. A hermaphrodite flower of Callitriche verna magnified the figure shows also the venation of the leaves. 

 Fig. 7. The same more magnified, the bracts having been removed to show the point of insertion of the stamen. 

 Fig. 8. Flattened glands on the stem of Callitriche pedunculata. 

 Fig. 9. A longitudinal section of the anther of Callitriche pedunculata. 



Fig. 10. The ovule of Callitriche verna at an early period, at or very near the time of flowering, showing that the raphe is scarcely half the length of the ovule ;— a, its point of attachment to the placenta: b, the foramen. The 



apex of the nucleus is visible through the semi-transparent primine. 

 Figs. 11. & 12. The same more advanced; — a and b, as before. The tissues being semi-transparent, the nucleus is seen incompletely filling the external tunic. 



Fig. 13. The mature seed showing that the raphe has scarcely increased in length, and that the undistended portion of the external tunic remains as a minute wing above the hilum ; a and b as before. . 



Fig. 14. A longitudinal section of the seed, showing the relative proportion of the embryo to the albumen and the length of the cotyledons, as compared with that of the radicle. The radicle is seen distant from the hilum by 

 one fourth of the longitudinal circumference of the seed. 



