Sp. M. bifureatum (Sw.) (v v.) ; M. dimorphum (Hook. 
and Grev., t. 145). 7 
This species is also a native of St. Helena, and is con- 
sidered by some to be only a form of the preceding. 
46,—Psomiocarpa, Presl (1849). 
Polybotrya sp., J. Sm.; Acrostichum sp., Hook. Sp. Fil. 
; Vernation fasciculate, erect, acaulose. Fronds sub-bipin- 
. natifid deltoid, the sterile 6 to 18 inches high, pilose, with 
articulate hairs, segments oblong lanceolate. Veins forked, 
venules free. Fertile fronds 8 to 12 inches high, long 
Stipate, slender, wholly contracted, forming a sporangi- 
ferous panicle. 
Type. Polybotrya apiifolia, J. Sin. 
Illust. Moore Ind. Fil., p. 1, fig. 8; J. Sm. Ferns, Brit. 
and For., fig. 36. S 
Ons.— This genus is founded upon a very peculiar Fern, 
a native of the Philippine Islands, and was originally 
placed by me under Polybotrya. Setting aside the con- 
traction of the fertile fronds, it might be taken for a small 
multifid species of Phegopteris or Lastrea. 
Sp. P. apiifolia (J. Sm.) (v v.) (Polybotrya apiifolia, 
` J. $m., 1841. Kunze in Schk. Fil., t. 62. Gard. in Field, 
Sert. t. 30, 31). 
47.—Ecexorria, Schott. (1843). 
Polybotrya sp., auct.; Acrostichum sp., Hook. Sp. Fil. 
Vernation sarmentose, short, sub-hypogeous. Fronds 
contiguous, stipate, pinnate, rarely bipinnatifid, 1 to 3 feet - 
high, generally viviparous; sterile pinne linear lanceolate, 
 Sub.entire or dentate, laciniated or pinnatifid, sinus mu- 
 eronate, Veins forked or pinnate, venules free. Fertile ` ` 
CHARACTERS OF TRIBES AND GENERA. 131 
