| In order to provide the basis of the genetic relationship among five kinds of plants in Gymnocarpium Newman and research the relations between Gymnocarpium jessoense (Koidz.) and Gymnocarpium remotepinnatum (Hayata) Ching, Many features in these five plants were studied thoroughly and described in this paper,including the leaf epidermal, Leaf epidermis, scales, sporangia, spores and tubular elements.1. Leaf epidermisIn this paper, we do a comparative study on the the characteristics of upper and lower epidermis,stomatal styles,the stomatal density. They have the similar characteristics of leaf epidermal cells in the five plants of Gymnocarpium Newman. Upper and lower epidermal cells have two types:long-shaped and stellate shape, anticlinal walls are irregularly uneven. Upper epidermal cells are about 90 x 45μm in size, and the lower are about 100×55μm in size, stomata size is about 35 x 25μm, Stomatal density in 29.3-37.0/mm2, Stomatal types are close, but no short paracytic, ribbon and the around, the number of other types are close except polar cells.2. ScaleThe rhizome scale structure of G. dryopteris (L.) Newman, G. oyamense (Bak.) Ching and G. robrtianum (Hoffm.) Newman are Lanceolate,the two others are ovate lanceolate;the edge of scales in Europe G. dryopteris (L.) Newman and G. robrtianum (Hoffm.) Newman have prominence but no glandular hair, on the contrary,the other have glandular hair, mesh shapes are similar to the five kinds of plants, all large mesh, long fusiform or rectangular cells.3. SporeRespectively, the five species of spore polar view and equatorial view are oval and kidney-shaped. Large differences show in spore surface ornamentation,others all have point-shaped ornamentation except Gymnocarpium oyamense (Bak.) Ching. However, different types of protuberances exist in the spore surface. In conclude, spore surface ornamentation reflect the differences between species within the genus. 4. Tracheary elementsThe five species have the same types of tracheary elements, which are all scalariform perforation plate,but the extents of residues in various pit membrane are different. G. dryopteris (L.) Newman and G. jessoense (Koidz.) Koidz.have a lesser extent pit membrane residues,and without the phenomenon of fully-retained Pit membrane.However, the extents of pit membrane residues in G. oyamense (Bak.) Ching,G. remotepinnatum (Hayata) Ching and G. robrtianum (Hoffm.) Newman are large,which have intact pit membrane areas. Therefore, we Speculated the former two species and the others are divided because of their intimate relationship and evolutionary status,which are showd that the former two have a more high evolutionary status.According to the all results in this study, we can draw that the species genetic relationships among G. Newma are close because of other similar morphological characteristics, though the five plants in indigenous Gymnocarpium Newma have large different in Leaf and spore morphology. It is inappropriate to devide Gymnocarpium Newman into Sect. Curranea (Copel.) Ching ex Z. R. Wang with one-pinnate leaves and Sect. Gymnocarpium Ching with two to there back pinnate, simply based on the leaf shapes. Though the study of various aspects of plant morphology in G. jessoense (Koidz.) Koidz. and G. remotepinnatum (Hayata) Ching, we believe that the two variants should be independent, so it is inappropriate that "Flora of Yunnan" consolidated them into one kind, and took the former as a synonym of the latter.
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