Mitrospermum compressum ( Will). 
509 
PLATE XXXIX. 
Drawings. 
Fig. 24. Part of a transverse section of a seed, showing the megaspore membrane (or carbonized 
tapetum) enclosing a tissue which may be a prothallus. D. H. S. 1803 (Dulesgate). x 57 circa. 
Fig. 25. Thick-walled, pitted elements of the sclerotesta in transverse section. U. C. L., S. 53 
(Shore), x 244 circa. 
Fig. 26. Base of a longitudinal section cut in the principal plane. The numbers indicate the 
position of the details drawn in Figs. 27, 28, 29, 30. v. b. = main vascular bundle ; v. b.' = branch 
bundle; sc. = sclerotesta ; b. = tissue of seed-base below branch bundles. U. C. L., R. 60 c (Shore). 
X 8^ circa. 
Fig. 27. Branch bundle cut longitudinally in its nearly horizontal course through the sclerotesta. 
(See ‘ 27 ’ in Fig. 26.) sc. — sclerotesta ; xy. = xylem ; ph. — phloem ; b. ~ tissue of seed-base. 
U. C. L., R. 60 c (Shore), x 400 circa. 
Fig. 28. Small part of the bundle drawn in Fig. 27, but further out, at the point where it is 
emerging from the shell and turning upwards (see ‘ 28 ’ in Fig. 26). Protoxylem occurs on the 
lower side of the bundle. U. C. L., R. 60 c (Shore), x 400 circa. 
Fig. 29. Short reticulate tracheide from just below the nucellus (see ‘ 29 ’ in Fig. 26). U. C. L., 
R. 60 c (Shore), x 400 circa. 
Fig. 30. Secretory cell and surrounding cells from seed-base tissue below the branch bundles 
(see ‘ 30 ’ in Fig. 26). U. C. L , R. 60 c. x 400 circa. 
M m 2 
