100 Palaeontologie. 



has been definitely established by a special geological investigation 

 undertaken for this purpose, two vascular plants have been found — 

 Rhynia Gwynne- Vaughani and Asteroxylon Mackici. The first of 

 these is dealt with in the present paper. It occurred in petrified 

 form so that it was possible to study its internal structure. The 

 plant formed a practically pure growth, and its erect cylindrical 

 stems stood closely crowded. They probably attained a height of 8 

 metres or more, and ränge from 6 mm to under 1 mm in diameter. 

 The plant was rootless and had no leaves, being composed entirely 

 of a system of cj^lindrical axes or stems. Its lower porlion consisted 

 of branched Underground rhizomes attached to the peaty soil by 

 numerous rhizoids. Branches of the rhizome turned gradually or 

 abruptly up and assumed the characters of aerid stems. The latter 

 were occasionally branched dichotomously and tapered gradually 

 upwards. They bore small hemispherical projections which were 

 non-vascular. On some of these bulges tufts of rhizoid-like pairs 

 were borne, while in other cases the projections developed into 

 adventitious branches, usually attached by a narrow base. Some of 

 these branches appear to have been readily detached, and their 

 occurrence free in the peat suggests that they served to propagate 

 the plant vegetatively. Some of the aerial axes ended in large 

 elongate-pointed sporangia with thick walls. The axes, on sectioning, 

 show an epidermis, a relatively wide cortex, and a simple central 

 cylinder, in which a solid Strand of tracheides is surrounded by a 

 zone of phloem. 



The plant is compared with Psilotum and with the Psüophytum 

 princeps of Dawson. It is proposed to include Psüophytum and 

 Rhynia in a distinct group of Pteridophyta, the Psilophytales. 



Agnes Arber (Cambridge). 



Stopes, M. C, New Bennettitean Cones from the British 

 Cretaceous. (Phil. Trans. Roy. Soc. Lond. Ser. B. CCVIII. p. 

 389—440. 6 pl. 25 text figs. 1918.) 



In the first part of this paper a description is given of a frag- 

 ment of a cone from the Gault of Folkestone Warren. For this 

 cone the author proposes the name of Bennettites albianus. Its nea- 

 rest ally is B. Morierei, Sap. & Mar. Its structure is well preserved 

 and the details of the integuments, interseminal scales, etc., are 

 fully described and figured. 



Carruthers' type specimen of Bennettites maximus has hi- 

 therto only been known by its external features. The author, how- 

 ever has obtained sections of it and describes its internal structure. 

 The most interesting feature is the occurrence of extremely young 

 cones which the author regards as bisporangiate. 



Agnes Arber (Cambridge). 



Wehrli, L., Der versteinerte Wald von Chemnitz. (Neujahrsbl. 

 Naturf. Ges. Zürich. 1915. 117. Stück, p. 1—21. 5 Taf. Zürich 1916.) 



Die verkieselten Araucarien stammen aus dem Dyas (Rotlie- 

 gendes). Die Struktur ist sehr gut erhalten, wenn auch die orga- 

 nische Substanz durch Si0 2 ersetzt ist. Zellwand und Zellinhalt 

 sind nur durch feine aber scharf begrenzte Helligkeits- oder Farb- 

 differenzen unterschiedbar; die ehemaligen Wände sind dunkler, 

 gelblich, die Ausfüllmassen der Zellen klarer, blasser. Jahresringe 

 sieht man, ebenso radiale unterbrochene Markstrahlen; die behof- 



