Institute of the Earth's Crust SB ＲAS，Irkutsk 664033，Ｒussia

In Jurassic sediments of Siberia，remains of Lycopodites are rare in occurrence． They are represented by two species: Lycopodites tenerrimus Heer，and L． (?) trichiatus Pryn． This paper presents an emended diag- nosis of the species L．(?) trichiatus Pryn．，and the descriptions of two new species: Lycopodites subulifolius sp． nov．，and L． baikalensis sp． nov． from the Early--Middle Jurassic sediments of the Irkutsk coal basin，Eastern Siberia，Ｒussia． As part of the research effort，it was found that the ecological preference of the new species was different: Lycopodites subulifolius sp． nov． grew in wet and open spaces，while Lycopodites baikalensis sp． nov． preferred to colonize young growth of bog forests．