932 RoBINSON: PTERIDOPHYTA OF THE HAWAIIAN ISLANDS 
Botanical Gardens of Berlin, Germany, for permission to study 
the Hawaiian ferns in the herbarium of the Royal Museum. 
PTERIDOPHYTA 
Plants (sporophytes) with well-defined vascular tissue, which 
in the homosporous series produce spores that grow into gameto- 
phytes which may be monoecious or dioecious, and in the hetero- 
sporous series produce megaspores and microspores; of these the 
megaspores grow into gametophytes that bear female organs 
(archegonia), the microspores into gametophytes that bear male 
organs (antheridia). As the result of the union of the egg cell 
in the archegonium and a motile male cell (antherozoid) from an 
antheridium, the sporophyte, ordinarily considered the plant, 
develops. Reproduction by some form of budding occurs both 
in the gametophyte and the sporophyte stage of the life history of 
many species. 
Spores in capsules (sporocarps) borne upon the rhizome. 1. SALVINIALES. 
Spores borne upon some aerial member of the plant. 
Sporangia not borne in the axils of scalelike leaves. 
Vernation circinate. 
Sporangia separate. 4. FILICALES. 
porangia coalescent (synangia). 3. MARATTIALES. 
Vernation erect or inclined. 2, OPHIOGLOSSALES- 
Sporangia b in the axils of scalelike leaves; these either 
distant or forming pact strobili. &, LyYCOpopliALESs. 
1. SALVINIALES 
Aquatic or subaquatic plants with horizontal, creeping Of 
floating stems, which bear sporocarps containing megaspores * 
microspores or both; leaves various. 
Plants floating; leaves with entire or 2-lobed blades folded in 
vernation. 1. SALVINIACEAE- 
gy Cae cus 
g ; or 2-4-foliate, circinate in 
vernation. 2. MARSILEACEAE- 
1. SALVINIACEAE 
Small floating plants, with a more or less elongated, sometimes 
branching axis. Leaves apparently 2-ranked. Sporocarp® - o 
more borne upon a common peduncle; megaspores and micro" 
spores in separate sori. 
Azolla sp. recently introduced to prevent the bree 
mosquitoes in the ditches along the rice fields. 
ding of 
