Psilopsida


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Noun1.Psilopsida - whisk ferns; comprising the family Psilotaceae or Psilotatae: vascular plants with no roots, partial if any leaf differentiation, and rudimentary spore sacs
class - (biology) a taxonomic group containing one or more orders
division Pteridophyta, Pteridophyta - containing all the vascular plants that do not bear seeds: ferns, horsetails, club mosses, and whisk ferns; in some classifications considered a subdivision of Tracheophyta
order Psilotales, Psilotales - lower vascular plants having dichotomously branched sporophyte divided into aerial shoot and rhizome and lacking true roots
References in periodicals archive ?
61-100 1909-1958 1959-1978 Algae 46 (3) 2 Fungi 74 20 (5) Lichens 4 0 Bryophytes 11 (4) 34 Lycopsida 20 1 Psilopsida 1 0 Sphenopsida 8 (1) 0 Pteropsida 52 (5) 0 Incertae sedis 13 (1) 0 Spermatophyta Gymnosperms 7 0 Angiosperms Monocotyledons 57 9 Dicotyledons 725 (9) 31 (1) TABLE 4.-Numbers of citations of selected terms in the subject indices of two cumulative index volumes Volumes 1-60 Volumes 61-100 1909-1958 1959-1978 A.