On the Structure of Schizaea malaccana. 
BY 
A. G. TANSLEY, M.A., 
Assistant Professor of Botany. 
AND 
EDITH CHICK, B.Sc., 
Quain Student in Botany , 
University College , London. 
With Plates XXV and XXVI and a Figure in the Text. 
T HE Schizaeaceae are certainly one of the most interesting 
families of Ferns from the point of view of their stelar 
anatomy. Within the limits of a very natural group of but 
four genera they appear to exhibit all the principal stages 
which recent theory has distinguished in the evolution of the 
stele — protostely with a solid xylem in Lygodium , and with 
a parenchymatous pith in Schizaea , solenostely in Anemia 
§ Anemiorhiza , and dialystely in the majority of the species 
of Anemia and in Mohria. There seems at present no reason 
for taking any other than the simple view that these four 
types represent progressive stages in the evolution of the 
stelar system, according to the general theory of Jeffrey 1 
and Gwynne-Vaughan. But in a case of this kind, where we 
have such a wide range of structure in a single family of but 
few genera, it is of importance to examine the anatomy of every 
1 Professor Jeffrey, however, considers that Schizaea represents a degeneration- 
stage from a siphonostelic type. See ‘ The Structure of the Stem in the Pterido- 
phyta and Gymnosperms,’ Phil. Trans., B, 1902, 
[Annals of Botany, Vol. XVII. No. LX VII. June, 1903.] 
