In conclusion I have to state, that very recently (since the drawings were completed, and as well as the specimens seen by such of my friends as were interested in fossil botany) Dr. Joseph Hooker has detected in the sporangia of a species referred to Lepidostrobus sporules, and those also united in threes. There are still, however, characters which appear to me sufficient to distinguish that genus from the fossil here described.
To the brief account here given of Triplosporite it is necessary to add a few remarks on some nearly-related fossils, chiefly Lepidostrobi, whose structure is now more completely known than it was when that account was submitted to the Society.
On the affinities of Lepidostrobus to existing structures, respecting which various opinions have been held, it is unnecessary here to advert to any other than that of M. Brongniart, which is now very generally adopted, namely, that Lepidostrobus is the fructification of Lepidodendron, and that the existing family most nearly related to Lepidodendron is Lycopodiaceæ. The same view is in great part adopted in my paper. But I hesitated in absolutely referring Triplosporite to Lepidostrobus, from the very imperfect knowledge then possessed of the structure of that genus. The specimens of Lepidostrobus examined by M. Brongniart were so incomplete, that they suggested to him an erroneous view of the relation of the supposed sporangium to its supporting bractea, and of the contents of the sporangium itself they afforded him no information whatever.
In concluding my account of Triplosporite, I noticed the then very recent discovery of spores in an admitted species of Lepidostrobus by Dr. Joseph Hooker, who, aware of the interest I took in everything relating to Triplosporite, the sections and drawings of which he had seen, communicated to me a section of the specimen in which spores had been observed, but which in other respects was so much altered by decomposition, that it afforded no satisfactory evidence of the mutual relation of the parts of the strobilus. The appearances, however, were such, that I hazarded the opinion of its being generically different from Triplosporite, an opinion strengtheued by M. Brongniart's account of the origin of the sporangium.
