Dcinaea and other Marattiaceae. 551 
For a good rfcimn? of the chief literature and an excellent 
general account of the Marattiaceae the reader is referred 
to the article in Engler and Prantl’s c Nattirlichen Pflanzen- 
familien. 5 
Other Histological Details. Certain of these were found 
to be of some use for generic and specific distinction, e. g. 
structure of sclerenchyma, but only to a limited extent. 
Finally the writer cannot express too strongly his great 
indebtedness to Dr. D. H. Scott for his constant interest, 
encouragement and advice during the course of the investiga- 
tion. Mr. L. A. Boodle also gave much assistance by helpful 
discussion and references to literature. 
EXPLANATION OF FIGURES IN PLATES XXII 
AND XXIII. 
Illustrating Mr. Brebner’s Paper on the Anatomy of Danaea and other Marattiaceae. 
Abbreviations. 
alb. albuminous cell (?) ; col. collenchyma ; cp . cavity parenchyma ; en. endo- 
dermis ; en.' internal endodermis ; It. leaf-trace ; me. mucilage canal ; ms. meri- 
stele ; mx. xylem ; mx.' xylem formed to inside of protoxylem ; pa. parenchyma ; 
px. pericycle ; ph . phloem ; pph. protophloem. 
Figs. 1-10 and 19 are from microtome series of Danaea simplicifolia seedlings. 
The radial walls of the endodermis are indicated conventionally. 
Figs. 1-4. From very young seedling showing formation of leaf-trace. ( x 242.) 
Fig. 5. Section from the same seedling showing departure of the first two leaf- 
trace meristeles and the approach of a root, (x 114.) 
Fig. 6. Section from a seedling showing abnormal preparation for the departure 
of several leaf-traces almost simultaneously. ( x 212.) 
Fig. 7. Section from the stem of a seedling with an abnormally long internode 
near the base. It clearly shows the endodermis round the stele and leaf-trace 
meristele. The stele is preparing for the departure of the next leaf-trace. ( x 182.) 
Fig. 8. Section from the same seedling. It shows an almost solenostelic stage 
owing to the junction of a root, (x 242.) 
Figs. 9 and 10. Sections from the same seedling showing departure of the next 
leaf- trace, (x 242.) 
