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PHYLUM TRACHEOPHYTA: 



TAXONOMIC SUMMARY 



Kingdom Plantae (Eng. plant) — plants 



Subkingdom Embryophyta (Gr. embryon, embryo + phyton, plant) — land plants 

 Phylum Tracheophyta (Gr. tracheia, windpipe + phyton) — vascular plants 

 Ptendophytes (Gr. pteris, fern + phyton) — fern plants 

 Subphylum Psilopsida (Gr. psilo, slender + opsis, appearance) — psilopsids 



Class Psilotae (Gi.psilo) — whisk ferns and allies 

 Subphylum Lycopsida (Gr. lykos, wolf + opsis) — lycopsids 

 Class Lycopodae (Gr. lykos + pod, foot) — lycopsids 

 Order Isoetales (Gr. isos, equal + etes, association) — quillworts 



Order Selaginellales (L. selago, kind of shrubby plant) — spike mosses or small club mosses 

 Order Lycopodiales (Gr. lykos + pod) — club mosses 

 Subphylum Sphenopsida (Gr. sphen, wedge + opsis) — sphenopsids 

 Class Equisetae (L. equus, horse + setae, bristles) — horsetails and scouring rushes 

 Order Equisetales (L. equus + setae) — horsetails and scouring rushes 

 Subphylum Pteropsida (Gr. pteris + opsis) — pteropsids 

 Class Filicinae (L.filic, fern) — ferns 

 Order Ophioglossales (Gr. aphis, snake + glossa, tongue) — adder's tongue and grape ferns 

 Order Marattiales (after J. Maratti, Tuscan botanist) — tropical ferns 

 Order Filicales CL.filic) — true ferns 



Order Marsileales (after L. F. Marsigli, Italian botanist) — water ferns 

 Order Salviniales (after A. Salvini, Italian scholar) — floating and mosquito ferns 

 Spermatophytes (Gr. spenna, seed + phyton) — seed plants 



Gymnosperms (Gr. gymnos, naked + spenna) — gymnosperms 

 Class Cycadae (Gr. kykas, coco palm) — cycads and fossil allies 



Order Cycadales (Gr. kykas) — cycads 

 Class Ginkgoae (Chinese ym, silver + hsing, apricot) — ginkgos 



Order Ginkgoales (Chinese j'iw + hsmg) — maidenhair tree or ginkgo 

 Class Coniferae (L. conus, cone +fero, to bear) — conifers and allies 

 Order Coniferales (L. conus +fero) — conifers 

 Order Taxales (L. laxus, yew tree) — yews 



Order Gnetales (Malay ^ncnom, name for plant) — Ephedra and allies 

 Angiosperms (Gv. angus,ve^s?.e\ + spenna) — flowering plants 

 Class Angiospermae (Gr. angos + sperma) — flowering plants 

 Subclass Dicotyledoneae (Gr. di-, two + kotyledon, cup-shaped cavity) — dicots 

 Subclass Monocotyledoneae (Gr. mono, one + kotyledon) — monpcots 



of a trend to present complexity in the ferns. Class 

 Filicineae. The remaining pteropsids, then, are 

 assumed to be living descendants of the interior line. 

 Support is given these premises by a very recent 

 fossil, Archaeuptens, a fern-like tree having a large 

 trunk. This Devonian "missing link" has fern-like 

 leaves and reproductive structures on a trunk much 

 like that of early spermatophytes. It is assumed that 

 Archaeuptens represented the interior line of ancestral 

 spermatophytes, but at a time predating the evolution 

 of true seeds. 



Among the spermatophytes the first main radiation 



probably provided the classes Cycadae, Coniferae, 

 and Ginkgoae; on the other hand, the Coniferae and 

 Ginkgoae may have evolved from definite Cycadae. 

 Although Angiospermae origin is not clear, their 

 ancestors probably evolved from the Coniferae. 



TRACHEOPHYTA (Vascular Plants) 



Diagnosis: comprise the vast majority of plants in 

 the form of trees, shrubs, and herbs; contain gameto- 

 phyte and sporophyte generations; gametophyte gen- 

 erally smaller than the sporophyte and functionally 



