Lepidocarpon sentence example
- In some of the heterosporous forms (Lepidocarpon, Miadesmia) the sporangia were sometimes surrounded by an integument; and since only a single megaspore attained maturity, the structure of the megasporangium suggests a comparison with an ovule.
- It is very doubtful whether any homosporous Lepidostrobi existed, but there is reason to believe that here, as in the closely allied Lepidocarpon, microsporangia and megasporangia were in some cases borne on different strobili.
- A more important deviation from ordinary Lepidostroboid structure is shown by the genus Lepidocarpon, from the English Coal Measures and the Lower Carboniferous of Scotland.
- Lepidocarpon affords a striking instance of homoplastic modification, for there i s no reason to suppose that the Lycopods were on the line of descent of any existing Spermophyta.
- In a male cone, probably belonging to wt Lepidocarpon Lomaxi, the microsporangia are provided with incomplete integuments.Advertisement
- The seed-like character of the organ is even more striking in Miadesmia than in Lepidocarpon.
- Another instance of the production of seeds in an extinct plant which further reduces the importance of this character as a distinguishing feature is afforded by the Palaeozoic genus Lepidocarpon described by Scott in 1901; this lycopodiaceous type possessed an integumented megaspore, to which the designation seed may be legitimately applied (see Palaeobotany: Palaeozoic).