321 
Vascular Anatomy of Platycerium. 
accessory medullary strands arise from the original dictyostele and 
that in the leaf-trace of the youngest leaf, no accessory bundles 
are present. Also the medullary strands close the leaf-gap and 
even the simple accessory strand in P. alcicorne (Fig. 3, 1-6) helps 
to do so. 
As regards the position of Platycerium among the Ferns, its 
vascular anatomy suggests a comparison with the Marattiaceae 
and the Pterideae. On general grounds it is most likely that 
Platycerium is related to the Matonineae. Diels (4, pp. 336-337) has 
placed Platycerium near Cheiropleuria , basing his comparison upon 
external resemblance, and Christ (3) groups these closely with 
Dipteris, a position which 1 am prepared to accept. But anatomi¬ 
cally Dipteris is relatively simple; its simple solenostele is replaced 
by several concentric solenostelic cylinders in Matonia. In many 
other phyletic lines, it may be seen how the solenostele becomes 
broken into a dictyostele. It would be quite consistent with the 
structural facts here described, if we were to consider Platycerium 
with its complicated dictyostele as the dictyostelic type of a series 
of which Dipteris and Matonia are the solenostelic types. Any 
near relationship however, with these ferns, cannot be established 
solely on the basis of the anatomical results obtained so far, but 
with continued investigation of facts other than those of stelar 
structure, supported perhaps by the discovery of some intermediate 
types, the position of Platycerium will probably be found near to 
the Dipteris-Matonia series. 
LITERATURE REFERRED TO 
1. Bower, F. O. “ The Origin of a Land Flora.” London, 1908. 
2. Bower, F. O. “ Studies in the Morphology of the Spore-Producing 
Members.” Phil. Trans. Roy. Soc., B, Vol. 192. 
3. Christ, H. “Die Farnkrauter der Erde.” 
4. Diels, L., in Engler and Prantl’s “ Natiirliche Pflanzenfamilien,” 
Teil 4. 
5. Hooker, W. J. “Garden Ferns.” 
G. Mettenius, G. “ Filices Horti Botanici Lipsiensis.” 
7. Seward, A. C. “On the Structure and Affinities of Matonia pectinata." 
Phil. Trans. Roy. Soc., B, Vol. 191, p. 171. 
8. Seward, A. C., and Elizabeth Dale. “ On the Structure and Affinities of 
Dipteris." Phil. Trans. Roy. Soc., B, Vol. 194, 
p. 487. 
9. Shove, R. F. “ On the Structure of the stem of Angiopteris evecta." Ann. 
of Bot., Vol. 14. 
10. Tansley, A. G. “ Lectures on the Evolution of the Filicinean Vascular 
System.” New Phytologist, Vol. 7, 1908. 
11, Thomas, E. N. “Some points in the anatomy of Acrostichum aureum." 
New Phytologist, Vol. IV, 1905. 
