

294 CONIFERALES INCERTAE SEDIS [CH. 



megasporophylls constitute the distinctive features of V. keuper- 

 iana: Schimper figures two strobili approximately 18cm. long 

 characterised by fan-shaped scales; the lamina has a fairly long 

 stalk gradually passing into a broad rounded distal portion with 

 a crenulate edge, the sinuses between the numerous crenulations 

 being continued as grooves over the face of the expanded portion 

 of the scale. No information is available as to the seeds. The 

 similarity in the general plan of the strobili, apart from the clearly 

 marked distinguishing feature of the megasporophylls, points to 

 a generic affinity between this species and V. Liebeana and V. hetero- 

 phylld. Schimper states that the strobili of V. Jceuperiana occur 

 in groups in contrast to the solitary cones of other types, and in 

 view of this distinction and the form of the cone-scales he employed 

 the generic name Glyptolepis for which Heer substituted Glypto- 

 lepidium 1 on the ground of the previous use of Glyptolepis for a 

 fossil fish. Schimper refers to this species the wood named by 

 Goeppert Araucarites keuperianus (= Dadoxylon keuperianum) but 

 there is no proof of actual connexion. Schenk 2 adopted the 

 generic name Voltzia and Potonie proposed a new term Voltziopsis 3 

 to be used in a provisional and wide sense for Voltzia Jceuperiana, 

 Cheirolepis Escheri Heer, Heer's Leptostrobus* and Nathorst' 

 Swedenborgia 5 (fig. 749), including species ranging from the Keupe 

 to Middle Jurassic strata in contrast to the Lower Triassic and 

 Permian range of typical representatives of Voltzia. The species 

 Cheirolepis Escheri, included by Potonie in his genus Voltziopsis 

 was founded by Heer on an imperfectly preserved scale from the 

 Lower Lias of Switzerland resembling the lobed cone-scales of 

 Cheirolepis Munsteri Schenk 6 . The genus Cheirolepis was in- 

 stituted by Schimper 7 as a substitute for BrachyphyUum for the 

 Rhaetic species B. Munsteri Schenk, the new name being chosen 

 because of the digitate margin of the cone-scales which are said to 

 bear single seeds. My former employment of Schimper's generic 

 term for sterile branches originally named by Phillips Brachy- 

 phyUum setosum 8 was hardly justifiable in the absence of sporo- 



Heer (77) ii. p. 72. 2 Schimper and Schenk (90) A. p. 290, fig. 199. 



Potonie (99) B. p. 304. 4 Heer (77) ii. p. 72. 



Nathorst (78) B. p. 30, PL xvi. figs. 612. 



Schenk (67) A. p. 187, PL XLIII. figs. 112. 



Schimper (72) A. p. 247. 8 Seward (00) B. p. 294. 



I 



