cycadofiliCales 



31 



Fig. 25. — Lagenostoma Lomaxii 

 (restored): the seed is surrounded 

 by a glandular cupula. — After 

 Oliver and Scott (48). 



THE MEGASPORANGIUM 



Numerous detached paleozoic seeds have been discovered, but 

 it must be remembered that they include the seeds of both Cordaitales 

 and Cycadofilicales. The seeds defi- 

 nitely connected with Cycadofilicales » "^ '^ 

 are comparatively very few, but the 

 structure of at least two of them is 

 known with remarkable completeness. 

 Lagenostoma.- — In 1903 Oliver 

 and Scott (39) announced that a 

 species of this seed genus is the seed 

 of Lyginodendron Oldhamium, and in 

 the following year the full account 

 appeared (48). The seed species was 

 a new one, and was described as Lage- 

 nostoma Lomaxii (fig. 25). The seeds 

 were not found in actual organic con- 

 nection with the foliage (Sphenopteris) 

 of Lyginodendron, but the numerous and 

 peculiar capitate glands borne on the 

 cupule correspond in every detail to those 

 on the vegetative organs of the associated 

 Lyginodendron, and represent a character 

 not possessed by any other associated 

 plant. There seemed to be no doubt 

 that the reference of the seed to Lygino- 

 dendron was fully justified, a conclusion 

 further confirmed by a comparison of 

 the anatomical details. Another species 

 of Lagenostoma (L. ovoides) was known; 

 and later Arber (51) described L. Kids- 

 tonii and L. Sinclairii from casts, but 

 important in that the seeds were con- 

 nected with branching axes that represent 

 naked branches of a frond (fig. 26). It is 

 evident, therefore, that the leaves of Lyginodendron were dimorphic, 

 one form being the familiar sterile fohage of the Sphenopteris type. 



Fig. 26. — Lagenostoma Sin- 

 clairii: two seeds on branches 

 of the rachis, each seed sur- 

 rounded by a cupule. — After 

 Aebee (51). 



