The President's Address. By Dukinficld H. Scott. 143 



hamium* in which the anatomical structure showed that the plant 

 was something else than a true Fern, long before any satisfactory 

 evidence as to the fructification was obtained. The anatomical 

 characters indicated a position intermediate between the Ferns and 

 the Cycads, a family of naked-seeded Phanerogams which still 

 retains some Fern-like traits. In this ease of Lyginodendron we 

 further found that the conclusions drawn from the vegetative 

 structure had since been more than confirmed by the observation, due 

 originally to Professor F. W. Oliver, that a previously unassigned 

 seed, Lagenostoma Lomaxi, presents structural features identical 

 with those of the Lyginodendron, with which it occurs in constant 

 association, while they are unknown in any other plant. The 

 evidence from structure, combined with that from association, 

 appears to leave no doubt that in this case a species with perfectly 

 typical Fern-foliage, of the Sphenopteris type, was nevertheless a 

 seed-bearing plant. The seeds of Lyginodendron are not rudimen- 

 tary, but highly differentiated, and almost on the same level of 

 organisation as those of living Cycads.f 



There are other species of Lagenostoma so closely allied to the 

 seed now referred to Lyginodendron oldhamium, that it is certain 

 that they too must have belonged to members of the same Fern- 

 like family. We will take two examples, both from the Lower 

 Coal Measures of Scotland, about to be fully described by 

 Mr. Newell Arber.J The seeds in question, to which the names 

 Lagenostoma Sinelairi and L. Kidstoni have been given, are only 

 known as yet in the form of casts, but they agree in important 

 characters with the species in which the structure is preserved. 

 In Lagenostoma Sinelairi, the seed, like that of Lyginodendron 

 oldhamium, is enclosed in a husk or cupule. These organs are 

 borne on the branches of a naked rachis, which can scarcely be 

 interpreted otherwise than as the reduced, fertile frond of some 

 Fern-like plant. 



In the other species, L. Kidstoni, there is no decisive evidence 

 for the presence of a cupule ; the characters of the seed, which is 

 conspicuously lobed at the micropylar end, show it to be a true 

 Lagenostoma. The seeds occur in great numbers on the surface of 

 a large slab, which is traversed in all directions by a branched 

 rachis, to the finer ramifications of which the seeds appear to have 

 been attached. Everything indicates that both these seeds were 

 borne on a frond of the Spihcnopteris type, modified, as is so often 

 the case among the Ferns themselves, in relation to its function as 

 the bearer of reproductive organs. 



* Journ. R. Micr. Roc, Dec. 1004, Proceedings, p. 725. 



t Oliver and Scott, "On the Structure of the Palasozoic Seed Lagenostoma 

 Lomaxi," Phil. Trans. K.S.(B) exevii. (1904) p. 193. 

 % In the Proceedings of the Royal Society, 1905. 



