(I50) A NEW JAPANESE ACROSTICHUM. 



Honokawa-yama in the province of Tosa. My specimens are from the above 

 locality and also from Nanokawa-mura in the same province. 



The creeping rhizome is 3 to 4 mm. thick, and often 1 5 to 20 cm. long, with 

 long branched roots which are tomentose with dark-brown hairs. Its cross-section 

 shows five or six sections of vascular bundles arranged more or less in the form 

 of a circle, one or two of which are elongated and curved, the rest are small and 

 oval. The scales which densely clothe the rhizome and the base of the stipe 

 are lanceolate, linear-lanceolate, or even linear, fringed with a few long hairs at 

 the margin, and attenuated into a long slender filament at the apex; they are 

 often 5 or 6 mm. long and 0.5 to i mm. broad. The stipes are winged and 

 canaliculate in front, their deciduous scales diminishing in size and number 

 towards the upper part, where they are much laciniated. The stipes are i to 

 1 . 5 mm. in diameter at the base. T^eir transverse section near the base presents 

 a somewhat semicircular outline, a thick ring of sclerenchyma inside the epi- 

 dermal layer, and usually three sometimes five oval sections of the vascular 

 bundles in the medullary parenchyma. The sterile fronds are much more 

 numerous than the fertile; their surface is very minutely punctato-squamulose 

 under the lens. Minute branched hairs or scales with a swollen cell at the 

 apex of the branches are found on both surfaces, but more abundantly on the 

 under. The frond is about 0.4 mm. thick. Its transverse section towards the 

 edge shows that its thickness decreases at the diaphanous margin which is 

 slightly or not all recurved. The young and small fronds are spathulate with a 

 round apex and a tapering base. The fertile fronds are similar to the sterile 

 except in their smaller size, longer stipe, and rather closer veins. There seems 

 to be but one of them in each stock. The sporangia are dark-brov/n, round 



