240 Scientific Intelligence. 



number of species of the genus Sphenophyllum have since 1804 

 been figured by various authors, and latterly with partial but not 

 always accurate demonstrations of their structure, the conflict of 

 opinions concerning the systematic position of this most discussed 

 genus has in general been waged on the evidence furnished by 

 the organization, ramification and foliation of the stems aud by 

 the superficial features of the cones. Recently, however, largely 

 through the efforts of M. Zeiller, we have been put in possession 

 of so many facts regarding the structure of the true fructification 

 of the genus as to throw great light on its relationship to the rest 

 of the vegetable world. 



The additional details of the organization of Bowmanites 

 [Volkmannia) Daiosoni Will., published, not long ago, by Prof. 

 Williamson, (Organization of the Fossil Plants of the Coal 

 Measures, Part XVIII, Philos. Trans. R. Soc, vol. 180, B, pp. 97- 

 101), so impressed M. Zeiller with their striking similarity to those 

 of the cone of S. cuneifolium (Stb.) Zeill. {S. erosum L. and 

 H.) in which he had in 1888 (Fl. foss. bassin houill. Valenciennes, 

 pp. 415-418, PI. LXIII, f. 4, 5, 10) detected the union of the bracts 

 in the verticil and the position of the sporangia on the latter, that 

 he reexamined the Valenciennes material, the result being the 

 announcement in the " Comptes Rendus" for July 11, 1892, of 

 his identification of Bowmanites Daiosoni as the cone of Spheno- 

 phyllum cuneifolium. This correlation of a cone, the structure 

 of which has been so far worked out by Williamson, was promptly 

 admitted by the latter in a short review of the subject in 

 "Nature" of November 3, 1892 (pp. 11-13). 



In the present memoir M. Zeiller briefly summarizes the re- 

 searches of Grand'Eury, Renault, and especially those of Will- 

 iamson with whose published results he makes a critical and thor- 

 ough comparison of all the available material. Although confined 

 mostly to opaque specimens he has been able to verify nearly 

 all ot Prof. Williamson's discoveries regarding the position and, 

 to some extent, the structure of the parts of the cone, besides 

 contributing much that is new. 



Briefly described, the cones of Sphenophyllum cuneifolium^ the 

 species best known, are 5-10 cm or more in length, 8-14 mm in 

 width, the diameter of the axis and the internodes each measur- 

 ing l-.5-2"25 mm each. The bracts, which are reflexed for a distance 

 at the base, then curved upward, 6-1 3 mm long, are united for a 

 distance from their origin, forming a funnel. The free ends of the 

 bracts are linear-lanceolate, slender, probably with a median 

 nerve. On the upper surface of these originate the pedicels 

 which curve outward, upward, and then in toward the axis', being 

 adnate for a little distance to the pendant sporangia. The 

 latter, oval, l-2 mm long and -75-1 -25 mm wide, are pluriseriate in 

 concentric rings between each pair of verticils, the outer rings 

 being higher than the inner. The sporangium wall is shagreened 

 and slightly spinous. The dorsal surface of the pedicel is, at least 

 near its extremity, formed of thick-walled cells which continue to 



