Lagenostoma is a genus of seed ferns (Pteridospermatophyta), based on ovules preserved in coal balls from the Six Inch Coal of the Hough Hill Colliery near Stalybridge, England.
Distinctive stalked glands enabled Oliver and Scott[2] to attribute these seeds to fernlike foliage of Sphenopteris hoeningshauseni in the same coal balls.
Lagenostoma has large (7–8 mm) ovules arranged in branching structures.
The genus name comes from the distinctive prepollen receiving structure of a cone blocked by a growing plug of tissue.
This article related to a Carboniferous plant is a stub.