Ill] SPOROGONITES 45 



among the Thallophyta rather than the Bryophyta. If the 

 sporanoium Avere sej^tate, the longitudinal septa might be 

 easily mistaken for a eolumella in material so imperfectly 

 petrified 1. 



^ [Tlicse criticisms seemed justified at the time they were written, but 

 the discovery by Kidston and Lang of a Middle Devonian plant, Ilornea 

 Lignieri, in which the si)orangium undoubtedly possesses a columella, puts 

 the whole question in a different light. The specimens of Hornea are 

 petrified and the whole organisation of the plant is shown; the columellate 

 sporangia are borne terminally on the dichotomous branches of a stem of 

 the Rlii/Nia type. While Hornea and Sporogouites are evidently quite 

 distinct, there is now every reason to believe that Halle's interpretation 

 of the structure of his fossil was essentially correct; the importance of his 

 discovery is manifest, whatever view may be taken of the affinities of the 

 plants in question. (See Kidston and Lang, On Old Red Sandstone Plants 

 showing Structure, from the Khynie Chert Bed, Aberdeenshire. Part ii. 

 Additional Notes on Rfiynia Gwynne-Vaugfiani, Kidston and Lang; with 

 Descriptions of Rfiynia major, n.sp., and Hornea Lignieri, n.g., n.sp. Trans. 

 Roy. Soc. Edinb. Vol. 52, Part ni. 1920, p. 603.) D. H. Scott.] 



