426 Hill . — The Morphology and Seedling Structure of the 
Fig. 9. A young bulb or corm at the end of the first vegetative period, showing the remains of 
the primary root (r), the remains of the absorbent and the scar of the aerial cotyledon. 
Fig. 10. A young plant during the second vegetative period, the corm ( cm ) is covered by hairs. 
The absorbent cotyledon with the seed and the remnant of the aerial cotyledon are seen. The first 
leaf (If) has developed. 
Fig. 11. A similar plant, a branched adventitious root has developed from the corm. 
Fig. 12. An older plant with the third leaf developed. 
Fig. 13. A young seedling, showing the relation of the two cotyledons within the seed; cf. 
Text-figs. 3 and 4, p. 420. 
Fig. 14. Median longitudinal section through the petioles of the cotyledon and the hypocotyl 
( hyp .) ; the junction of the two bundles below the plumule ( pi .) is well seen. Mag. x 300. 
Fig. 15. An older plant, two green plumular leaves and several adventitious roots have developed 
from the tuber. 
Fig. 16. Transverse section of a germinating seed about the age of Fig. 6 ; the remains of the 
pericarp and testa (pt.) surround the perisperm (pm.). This is bounded internally by the endosperm — 
represented by a darkly stained band — and within the cavity of the endosperm lies the lamina of the 
absorbent cotyledon (^.), its dorsi-ventral structure is still preserved and the midrib is indicated. 
Mag. x 120. 
Fig. 17. Transverse section of the primary root at the base of the hypocotyl of a seedling 
similar to Fig. 7. The small diarch xylem plate consists of about two lignified elements (x.). en = 
endodermis ; ///.=phloem. Mag. x 300. 
Figs. 18-28. P. parvifolia, C. DC. 
Fig. 18. A fruit in a slightly oblique median longitudinal section, showing the short style (s) 
with the micropyle (m) pits in the outer layer of the pericarp with groups of gland-cells (g) at their 
bases ; (pm.) perisperm ; (e.) endosperm. Mag. x 64. 
Fig. 19. A pit with its group of four gland-cells in a section parallel to the surface of the 
fruit. Mag. x 300. 
Fig. 20. Two pits in longitudinal section, showing the gland-cells, with some of their contents 
stained by eosin. Mag. x 300. 
Fig. 21. A germinated seed with the petiole of the absorbent cotyledon (c t ), the rest of the 
seedling has been lost. 
Fig. 22. The absorbent cotyledon with its petiole and club-shaped lamina (/.), the seed-coats, 
&c. seen in Fig. 21 have been dissected away; cf. Text-figs. 5 and 6, p. 420. 
Fig. 23. A young plant with the remnants of the two cotyledons (c lf c.p, the first leaf has 
developed, and there is a basal tuft of roots. 
Fig. 24. An older bulb with several leaf-scars and two leaves. About nat. size. 
Fig. 25. A slightly older stage with well developed roots. 
Fig. 26. A young bulb with an inflorescence (s.). 
Fig. 27. A well developed plant, the corm (cm.) bears a terminal crown of leaves and 
inflorescences (s.) and a large basal tuft of roots. Nat. size. A. W. Hill, No. 181 in Herb. Kew. 
Fig. 28. An old corm. About nat. size. 
Fig. 29. P. verruculosa , Dahlst. The fruit in median longitudinal section to compare with 
that of P. parvifolia ; the pericarp is very deeply pitted, and the innermost layer consists of large 
cells; the wall of the testa is thick. Lettering as in Fig. 3. Mag. x 64. A. W. Hill, No. 182, 
Herb. Kew. 
Fig. 30. P. umbilicata , H. B. and K., a seedling with the seed in section; the absorbent 
cotyledon (^) is more or less club-shaped and surrounded by the endosperm (e.). Mexico, No. 631, 
Bourgeau, in Herb. Kew. Cf. Fig. 21 and Text-figs. 5 and 6, p. 420. 
PLATE XXX. 
Fig. 31. P. umbilicata , H. B. and K. A fruit in median longitudinal section, the small pits 
have only a single gland-cell at their base. The narrow pericarp and almost circular seed should 
be noted ; cf. with P. parvifolia. Mag. x 64. Mexico, No. 802, Parry and Palmer, in Herb. Kew. 
