1 86 Yapp . — Two Malayan ‘ Myrmecophilous 3 Ferns. 
he is perfectly correct. The caudex (perhaps in itself 
abnormal, but the same in all three) and the fertile seg- 
ments are abnormal, inasmuch as there is a suppression of 
the substance of the frond between the sori ; the consequence 
is that these segments form marginal lobes, which in a dry 
state are turned back on the upper side of the frond (as the 
fructifications of Nephroma resupinata among the Lichens). 
The venation is the same in all three ; and if we can believe 
that Lecanopteris carnosa is a state of P. sinuosnm , Wall., 
there will be no difficulty in referring Blume’s L. pumila to 
L. carnosa l 
It is with the anatomy, biology, and systematic position of 
Lecanopteris carnosa , Bl., and Polypodium sinuosum, Wall, 
(two of the Ferns referred to above) that this paper proposes 
to deal. 
The systematic position of these two Ferns will be discussed 
later, as well as the question of the identity of L. carnosa, , BL, 
and L.pumila, Bl. ; but in the meantime it is interesting to 
note, in view of the passage quoted above, that although 
Lecanopteris carnosa and Polypodiitm sinuosum are beyond 
doubt specifically distinct, and differ widely in external 
appearance, yet an examination of their internal structure 
reveals the fact that, after all, their resemblances are more 
remarkable than their differences, and that instead of being 
placed in separate genera, they must be recognized as closely 
allied species. 
That being so, Lecanopteris carnosa , Blume, will be in future 
referred to in this paper as Polypodium ( Lecanopteris ) car - 
nosum , (Blume), or, to avoid needless repetition, as Polypodium 
car no sum. 
Both of these Ferns belong to the so-called myrmecophilous 
plants. Their thick, fleshy rhizomes are tunnelled by a system 
of galleries, which are invariably inhabited by colonies of 
ants. They are both epiphytes of the Malay region. 
Polypodium car no sum grows only on the higher branches 
of trees, and usually, at all events, on fairly high mountains. 
It forms thick encrusting masses, often several feet in length, 
