122 Brebtip'r — On Dcinaect simplicifolia , Rndge . 
EXPLANATION OF FIGURES IN PLATE IX. 
Illustrating Mr. Brebner’s paper on the prothallus and embryo of Danaea 
simplicifolia , Rndge. 
Figs, i and 2. Prothalli. Nat. size. 
Fig. 3. Young plant attached to prothallus, with only the cotyledon expanded: 
an ., developing antheridia. x 2%. 
Fig. 4. Similar to preceding: pr., prothallus. Nat. size. 
Fig. 5. Young plant still attached to prothallus, pr., showing three young leaves 
and the bases of the two first. Nat. size. 
Fig. 6. Rhizoid, rh., of prothallus, pr. x 50. 
b 7. Young antheridium originating from adult cell of prothallus. x 350. 
Fig. 8. Young antheridium, slightly older than the preceding, and showing the 
first division of the mother-cell of the sperm-cells. x 350. 
Fig. 9. Young antheridium, similar to preceding, seen from below: m., peri- 
pheral cells. x 350. 
Fig. 10. Cover-cells of preceding, seen from above. X350. 
Fig. 11. Cover-cells of empty antheridia, seen from above. The dotted lines in 
one of the sets indicate the thickness of the cells seen in perspective. x 350. 
Fig. 12. Nearly mature antheridium : m., peripheral cells. x 350. 
Fig. 13. Mature archegonium : ov., ovum; sp., probably a spermatozoid. X350. 
Fig. 14. Mature archegonium : ov., ovum ; n.c., neck-cells, x 350. 
Fig. 15. Vertical section of a youngish embryo, not quite median: b.b. basal 
wall ; II. II, transversal wall. Arrow indicates direction of growing-point of 
prothallus. X250. 
Fig. 16. Vertical section of an older embryo: si, growing-point of stem; 
I., cotyledon. x 200. 
Fig. 17. Growing-point of stem of the same. X400. 
Fig. 18. Vertical section of a still older embryo: si, growing-point of stem; 
L., cotyledon ; r. root. x 100. 
Fig. 19. Growing-point of stem of the same. X400. 
Fig. 20. Transverse section of stele of the stem at junction of first and second 
leaf-traces : L. b., cotyledon bundle ; en. endodermis. x 400. 
