VIII, c, 3 Copeland: On Phyllitis in Malaya 153 
If Asplenium epiphyticum bears a fertile vein on the lower 
side of the main vein, its sorus will face one in the normal 
position, and produce a double sorus of the type of Phyllitis. 
I have only once seen such a vein; the resulting fructification 
is shown in Fig. 7. 
Asplenium epiphyticum is not only very near the common 
ancestor of Phyllitis and Stenochlaena, but it stands in the 
same position in regard to the simple-leaved group in its own 
genus, sometimes separated to form such genera as Neottopteris 
and Thamnopteris, This was first suggested to me by certain 
Bornean species, then new, which are intermediate in texture 
and general appearance between Asplenium epiphyticum and 
A. squamulatum and the A. Nidus group. Examination of the 
spores disclosed a remarkable common character, in the extreme 
spininess. This spininess is present in Phyllitis Durvillei, and 
is merely suggested in Stenochlaena. 
SUMMARY 
The genus Diplora is invalid, because founded on a misconcep- 
tion of the structure, the actual structure being that of Phyllitis. 
The genus Triphlebia is invalid, because founded on inconstant 
"characters," and again in part on illusory ones. 
Phyllitis, including the above, has only three well-defined 
species in the Malay-Polynesian region : 
p. SCHI20CARPA (Copel.) v. A. v. R. 
P. LONGI FOLIA (Presl) 0. Ktze. 
P. DURVILLEI (Bory) 0. Ktze. 
The most primitive species of Phyllitis is P. Durvillei. It in 
turn is descended from Asplenium, from A. epiphyticum or 
some similar form. 
Asplenium epiphyticum is an extant fern which very nearly 
represents stages in the ancestry of the genus Phyllitis, the 
genus Stenochlaena, and the Nidus group in Asplenium. 
Note. — The connection of Phyllitis with Asplenium, and the 
explanation of the phylogeny of Phyllitis, so completely that 
the specific identity of the forms connecting them has been 
questioned, does not demand that the genus Phyllitis be given up. 
It is simply the realization, in one detail, of the general aim 
of the study of systematic biology and bionomics. We would 
still want to recognize genera and species, if the tree of life could 
be reproduced in every detail. 
