310 CHARACTERS OF TRIBES AND GENERA. 
exterior venules free; the costal anastomoses transverse, 
elongated, and sporangiferous. Sori oblong, contiguous, 
forming a sub-costal medial row. Sporangia immersed. 
Indusium vaulted. 
Type. Blechnum radicans, Linn, 
Ilust. Hook. and Bauer Gen. Fil, t. 17; Moore Ind. 
Fil, p. 33 B., fig. 1; J. Sm. Ferns, Brit. and For., 
fig. 104; Hook. Syn. Fil., t. 4, fig. 36 a. 
Oss.—This is a well marked genus which in the “ Species 
Filicum” is represented by six species, three of which I, 
however, exclude from true Woodwardia, as I consider them 
sufficiently distinct to warrant their adoption under the 
two following genera, 
The species here restricted to Woodwardia are remark- 
able for producing numerous viviparous buds, which readily 
become plants. 
Sp. W. radicans, Sm. (v v.) ; W. orientalis, Sw. (v v.) ; 
W. Japonica, Sw. (v v.). 
The two latter species are natives of China and Japan ; 
the first is found in the South of Europe, Madeira, Azores, 
Java, Mexico, California, Guatemala, and Northern India. 
176.—Lormszri, Presl (1849). 
Woodwardia, Hook, Sp. Fil. 
Vernation uniserial, sarmentum hypogeous. Fronds 
distant, sinuose-pinnatifid or sub-pinnate, 1 to 1} feet high, - 
the fertile contracted. Veins of the sterile frond uniform ` 
reticulated ; fertile segments rachiform, costal anastomoses ~ 
transverse-elongated, sporangiferous. Sori oblong-linear, - 
contiguous, forming a costal row. Indusium veulied: 
Type. Acrostichum areolatum, Linn. 
