278 TAKEDA—ASIATIC POLYPODIUMS. 
P. nudum has received more names from Wallich, namely 
P. gladiatum and P. Wightianum. An examination of the 
Wallichian Herbarium, now in possession of Kew, together with 
other specimens distributed by Wallich, has convinced the writer 
that P. Wightianum is exactly identical with the typical P. 
nudum, while the — name was given to a narrow-leaved form 
of the same specie 
In addition a this complication in nomenclature, Kunze 
described in 1850 P. nudum under the name of P. leopteris.* 
This name was accepted by Mettenius in 1856,+ but in the fol- 
lowing year was reduced to P. sesquipedale, Wall. 
__- In 1851, Kunze published another new species called P. 
nudiusculum.§ According to the author, this fern is closely 
allied to P. nudum, while Christensen || tells us that it is partly 
P. lineare and partly P. simplex. As far cs the writer has been 
able to make out from the original description, P. nudiusculum, 
Kze. seems to be conspecific with P. nudum, as several other 
botanists consider. 
The confusion of P. nudum with P. excavatum may be ex- 
cusable, but how this species has been confounded with P. 
lineare, P. loriforme, or P. Gueintzii is almost inconceivable. 
P. nudum can easily be distinguished from any form of P. lineare 
by the ramenta on the rhizome being ovate, acuminate, entire, 
and brownish in colour, while the ramenta of P. lineare are 
subulate, long-acuminate, ciliate-dentate, and black in colour. 
The second point of distinction is that the sori of P. nudum 
are situated close to the midrib and usually reach more than 
half way down the frond, whereas those of P. lineare are gener- 
ally between the midrib and the margin or slightly nearer the 
margin, and extend but seldom to the base of the frond. The 
texture of the frond varies to some extent ; it is usually sub- 
coriaceous and thinner than in P. lineare, or in some cases still 
thinner. However, the veins are always hidden, as in P. lineare. 
Since the frond persists through the winter, it rolls up in the dry 
weather, as may often be seen in the herbarium specimens 
in the margin being revolute. When a specimen is collected 
in the dry season and pressed as it is, the plant assumes the 
condition of P. contortum, Christ. 
The dimension of the frond is extremely variable. In a 
small specimen the frond may be about ro cm. long and 7-10 
* Linnaea, xxiii, p. 319 (1850). 
t Fil. Hort. Lips. p. 36, tab. 25, fig. 37-39 = 
$ Polypod. P. or ‘859. a ettenias fordions nly wrong in — Wallich’s 
name for this the sy 
but not to P. sonnibadals Wall. 
§ Linnaea, xxiv, p. 253 (1851). 
ee Fil. p. 548 (1906). 
J S y um, 
