596 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fossil Osmundaceae and Zygopterideae.*— W. T. Gordon writes on 

 the relation between the fossil Osmundaceae and the Zygopterideae. 

 Anatomically they are almost indistinguishable ; and this fact, taken in 

 conjunction with their geological positions, points to the conclusion 

 that the Zygopterideae diverged from the parent stock before the 

 Osmundaceae did, and subsequently dropped out of existence. 



Fossil Ferns of France.f — 0. Lignier publishes a sixth paper on the 

 fossil plants of Normandy, treating of the Jurassic flora of Mamers 

 (Sarthe). The Pteridophyta are represented by Lomatopteris, Linopteris, 

 Equisetites. 



F. Pelourde % publishes observations on some fossil plants of the 

 Autun strata, namely, Stipitopteris sp. and Botryopteris antiqua, which he 

 describes and compares with other known specimens. 



Suspensor in Helminthostachys.§ — W. H. Lang indicates in a note 

 the discovery of a suspensor in Helminthostachys zeylanica. The sus- 

 pensor is multicellular, two tiers being visible. It closely resembles the 

 suspensor of Botrychium obliquum, but is attached to the proth alius by a 

 large foot. The possession of a suspensor is not a peculiarity of the 

 Lycopodiales, but has been demonstrated in Botryehium, Helmintho- 

 stachys, and Dansea. 



Schizoneura paradoxa.|| — R. D. Vernon gives a description of frag- 

 ments of Schizoneura paradoxa Schimper and Mougeot found in the 

 Bunter of Nottingham, an Equisetaceous plant of exceptional interest as 

 being the first evidence of contemporary life in the Bunter rocks of 

 England. 



L. J. Wills I publishes some notes on the genus Schizoneura, and 

 shows that the species fall into two groups — Neocalamites and Schizo- 

 neura proper — but what relation these bear to the Calamites and to the 

 modern Equisetum must remain a secret until more is known of the in- 

 ternal structure and of the fructification. 



Assimilating-tissue of Fossil Ferns (Calamites).** — H. H. Thomas 

 describes the assimilating tissues of some Coal Measure plants, especially 

 those of the Calamocladus section of the Calamites. The leaves are 

 small, short, cylindric, and were borne in whorls on long, slender, 

 pendulous stems. The central vascular bundle is surrounded by the 

 bundle-sheath and then by palisade tissue, the isolated cylindric cells of 

 which are situated radialiy. The air-spaces being very large, the 

 mesophyll is very spongy. The stomata are confined to the adaxial 

 (probably lower) side of the leaves. The stomata closely resemble 

 those of Equisetum. The bundle-sheath is rendered conspicuous by the 

 large mass of its opaque carbonaceous contents. No phloem nor sieve- 

 tubes are obvious. The bundle-sheath doubtless functioned as the path 

 of conduction for the products of assimilation in these small leaves. The 



* Proc. Cambridge Phil. Soc, xv. (1910) pp. 398-400. 



f Mem. Soc. Linn. Normandie, xxiv. (1910) 48 pp. (pis. and figs.). 



% Ann. Sci. Nat., xi. (1910) pp. 361-71 (figs.). 



§ Ann. Bot., xxiv. (1910) p. 611. 



|| Proc. Cambridge Phil. Soc, xv. (1910) pp. 401-5. 



«([ Tom. cit., pp. 406-10. 



Proc. Cambridge Phil. Soc, xv. (1910) pp. 413-15. 



** 



