Early Devonian land plants from Bathurst Island, district of Franklin

Abstract

Two collections of Early Devonian land plants belonging to the Zosterophyllophytina and Lycophytine, from Bathurst Island, District of Franklin, are described and figured. The assemblage from GSC plant locality 8370 contains Bathurstia denticulata n. gen. et n. sp., Rebuchia capitanea n. sp., Sawdonia orna ta (Dawson) Hueber, Drepanophycus spinaeformis Goppert, cf. Bathurstia sp., and an unnamed zosterophylloid axis. A specimen of Sawdonia ornata is described from GSC plant locality 8376. The plants are of Siegenian and Emsian age respectively on the bases of the invertebrate fossils and dispersed plant spores with which they are associated. The Siegenian plants represent the earliest record thus far of land plants in Canada and the first report of Early Devonian plants from the Canadian Arctic. The presence of a cuticle was demonstrated for all but one of the plants. Evidence of a vascular strand composed of tracheids was obtained only from the specimen of Drepanophycus. Those fossils with a cuticle but lacking a xylem strand should be described as those of land plants and not as those of land vascular plants. The probable sequence in the origin of cuticle, cutinized spores, vascular strand composed of tracheids, and stomata, is briefly discussed.