TAKEDA—ASIATIC POLYPODIUMS. 275 
3. P. Lewisii, Baker. 
This is a very small fern measuring about 4-10 cm. in length. 
It is undoubtedly related to the preceding species; it differs, 
however, in the main, by the margin of the frond being strongly 
revolute, so that it completely conceals the sori, while in the 
other plant the sori are, at all events, quite visible. 
This seems to me a rare species, having been found by Dr. 
Shearer in Kiukiang, Kiangsi, in 1873, and described 8 Mr. 
Baker in 1875 ; * it has not been collected since. 
4. P. oblongisorum, Christensen. 
When describing this species under the name of P. sub- 
integrum, Baker,t the author states that his plant comes very 
close to P. soridens, Hook. He seems to have noticed only the 
position of the sori, which, in the mature condition, appear to 
project beyond the margin of the frond, in consequence of the 
free parts of the margin becoming strongly revolute. These two 
species are, however, not closely related at all, since P. soridens 
belongs to J. Smith’s Phymatopsis, while Baker’s plant is a 
Eupleopeltis. As a matter of fact, P. oblongisorum, C. Chr. is 
allied to P. etlophyllum, Diels, from which it can easily be dis- 
tinguished by the narrower and less revolute frond and the 
marginal sori. 
Only the type specimen from Yunnan (Henry, n. 9194, part.) 
has been examine 
The name has been altered to’P. oblongisorum, C. Chr.,t 
because subintegrum has been occupied by another plant. 
5. P. subimmersum, Baker. 
This species somewhat resembles P. lineare var. loriforme, 
Takeda, from which it differs - ee the margin slightly 
sinuate, with a sinus near each so 
This fern from China was fist described by Mr. Baker in 
1895 under the name of P. subimmersum. In 1906 the same 
author gave a second name, P. xiphiopteris, to an identical form, 
and another name, P. mengizeanum, to a broad-leaved form 
of the same species 
In regard to the width, the frond is liable to variation. 
While the usual breadth of the fronds is 10-15 mm., there 
‘sometimes occurs a frond not exceeding 8 mm. or even less 
broad. The plant described as P. mengizeanum possesses an 
exceptionally broad frond attaining 2 cm. in width. 
* Journ. Bot. iv, p. 201. + Kew Bull. (1898), p. 231. 
t Ind. Filicum (1906). 
