MAESILEACEAE. 475 



3. Anemia adiantifolia (L.) Sw. Syn. Fil. 157. 1806. 



Osmunda adiantifolia L. Sp. PI. 1065. 1753. 



Ornithopteris adiantifolia Bernh. Neiies Journ. Bot. Schrad. 1^: 50, 1806. 



Eootstock creeping, densely hairy. Leaves distichous, close together, sub- 

 coriaceous, 1.5-8.5 dm. long, 2-4-pinnate, ovate to subpentagonal in outline, the 

 straw-colored stipe usually as long as the blade or longer; pinnae several or 

 numerous, the lower the longer, the ultimate segments commonly close together, 

 deltoid to oblong or ovate, obtuse or acutish, entire or few-toothed, 4-15 mm. 

 long. Fertile leaf like the sterile, but the 2 lower pinnae transformed into 

 panicles of sporanges, which are slender-stalked and erect. 



In sink-holes and in pine-lands, Abaco, Great Bahama, Andros, New Providence, 

 Eleuthera, Cat Island: — Florida; West Indies; Central America; northern South 

 America. Maiden-hair Akemia. 



Order 2. SALVINIALES. 



Aquatic or uliginous herbs with entire or 2-lobed, filiform, or 4-foliolate 

 leaves. Spores of two kinds and sizes (microspores and macrospores) con- 

 tained in sporocarps. 



Family 1. MARSILEACEAE R. Br. 



Perennial herbaceous plants rooting in mud, with slender creeping 

 rootstocks and 2- or 4-foliolate or filiform leaves. Asexual propagation con- 

 sisting of sporocarps borne on peduncles which rise from the rootstock near 

 the leaf-stalk or are consolidated with it, containing both macrospores 

 and microspores. The macrospores germinate into prothallia which bear 

 archegonia, while the microspores grow into prothallia bearing antheridia. 

 Three genera and some 45 species of wide distribution. 



1. MARSILEA Sp. PL 1099. 1753. 



Marsh or aquatic plants, the leaves commonly floating on the surface of 

 shallow water, slender-petioled, 4-foliolate. Peduncles shorter than the petioles, 

 arising from their bases or more or less adnate to them. Sporocarps ovoid or 

 bean-shaped, composed of two vertical valves with several transverse compart- 

 ments (sori) in each valve. [Name in honor of Giovanni Marsigli, an Italian 

 botanist, who died about 1804.] About 40 species, widely distributed. Type 

 species: Marsilea quadrifolia L. 



Leaflets obliquely linear-oblanceolate. 1. M. NasJiii. 



Leaflets broadly obovate-cuneate. 2. M. vestita. 



1. Marsilea Nashii Underwood, Bull. N. Y. Bot. Gard. 4: 137. 1906. 



Plants forming compact dense mats in sandy soil. Stems short, slender, 

 smooth or with a few appressed slender hairs, forming nodes at intervals of 

 3-10 mm.; leaves rising in clusters from short lateral branches; petioles fili- 

 form, 5-8 cm. long; leaf -divisions narrow, cutlass-shaped, 10-12 mm. long, 2 

 mm. wide, sparsely covered with white appressed hairs; sporocarps abundant, 

 solitary on short peduncles, compressed-oval, averaging 7X4X2 mm., the 

 raphe ending in a short, straight tooth with a second similar basal tooth 1 mm, 

 beyond, the surfaces covered with appressed hairs, becoming smoother with 

 age; sporangia about 12 pairs, elongate-oval, 4 mm. long by 1 mm. thick, the 

 gelatinous stalk 2.4 cm. long; macrospores about 8-10 in each sporangium, 

 oval; microspores numerous, globose. 



Smith's Thatch Pond, Inagua. Endemic. Nash's Peppeewort. 



