Marsilea MARSILEACEAE-OPHIOGLOSSACEAE Azolla 



1. Marsilea Linn. Pepperwort MM (P'in Shu) 

 Plants growing in shallow water at least part of the year, with creeping rhizomes 

 rooting in mud, and lvs. commonly floating on the surface: lvs. slender-petioled, 

 quadrifoliolate: sporocarps borne on short peduncles arising on or near the base of 

 the stipes, ovoid, solitary to several: two rows of sori borne on a gelatinous ring filling 

 the sporocarp, each sorus bearing a row of megasporangia and many microsporangia. 

 67 species. (Named for Luigi Fernando Conte Marsigli, 1658-1730, an early Italian 

 naturalist.) 

 1. Marsilea quadrifolia Linn. (G. M. 51) Petiole 6-10 cm. long or more; VIII-XI; 

 sporocarps pubescent. North America, Europe, Asia; locally in An., Che., Ki., Ku. 

 Edge of ponds. 



6. SALVINIACEAE \%%m^ (Huai Yeh P'ing K'o) 



Small floating plants: rhizome horizontal, branching freely: sporangia of two kinds, 

 borne in sporocarps. Two genera, often considered as representing two separate 

 families. 



Key to the Genera 



Lvs. 1-2 cm. long, bright green; midrib distinct 1. Salvinia 



Lvs. about 1 mm. long, reddish 2. Azolla 



1. Salvinia (Michx.) Adans. \%MWU (Huai Yeh P'ing Shu; Locust-leaf 



Duck-weed Genus) 



Small floating plants with slender rhizomes which are easily broken, thus rapidly 

 reproducing vegetatively, and often covering whole ponds: true roots absent; lvs. 

 apparently 2-ranked, floating, a third series root-like and submersed: sporocarps globose, 

 arranged in clusters arising from the basal divisions of the filiform leaves, some 

 containing microsporangia, others megasporangia. 8 species. (Named for Antonio 

 Maria Salvini, 1633-1729, professor of botany in Florence, Italy.) 

 1. Salvinia natans (L.) All. (G. M. 51) Lvs. 10-15 mm. long; fr. VII-XII; papillae 



with tufts of free hairs. Europe, Asia, North America; locally in An., Che., Ki., 



Ku. Floating on ponds. 



2. Azolla Lam. Water- Velvet WX^LM (Man Chiang Hung Shu; 

 Whole River Red Genus) 



Small floating ferns turning purplish in the fall: lvs. alternate, 2-lobed, the upper 

 lobe floating, the lower lobe submersed: roots single or clustered: sporocarps of two 

 kinds; the microsporocarp larger, globose, containing many stalked microsporangia 

 each of which contains 2-8 massulae, the microspores imbedded in the massulae, the 

 massulae bearing trichomes; megaspore ovoid, containing a bell-shaped basal portion 

 and 3 apical floats. 7 species. (Greek term meaning "to destroy by drying," in 

 reference to the aquatic habit.) 

 1. Azolla imbricata (Roxb.) Nakai (DeV. F. 44) Lvs. 1.2-1.4 mm. long; fr. LX-XI; 



3-5 trichomes on one side of massula, and 2 tiers of floats. Asia; locally in An., 



Che., Ki., Ku. Floating on ponds. 



7. OPHIOGLOSSACEAE Adder's Tongue Family Mffi'b^& 

 (P'ing Erh Hsia Ts'ao K'o) 

 Succulent herbs; two epiphytic, the others terrestrial; stem short, fleshy: leaves 



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