资料来源 : pyDict

松叶蕨纲

资料来源 : WordNet®

Psilopsida
     n : whisk ferns; comprising the family Psilotaceae or
         Psilotatae: vascular plants with no roots, partial if any
         leaf differentiation, and rudimentary spore sacs [syn: {class
         Psilopsida}, {Psilotatae}, {class Psilotatae}]