TH. G. HALLE. A. GYMNOSFERM WITH CORDAITEAN-LIKE LEAVES. 3 



into branches. This is probably due to the mode of preserva- 

 tion. In the living plant the veins, no doubt, traversed the 

 whole lamina without dividing or anastomosing. 



The affinities of the present fossil are very obscure. It 

 is only in recent time that plants of a similar habit have 

 been recorded from the Mesozoic rocks. In the Palaeozoic 

 there existed, in the Cordaitales, a group of plants with Mo- 

 nocotyledonous-like leaves, spirally arranged on the shoot. 

 There are some facts which seem to indicate, that the Cor- 

 daitales persisted also in the Lower Mesozoic. Compter 1 

 described in 1894 some specimens from the Keuper under 

 the name Cordaites keuperianus, and Lignier 2 has found that 

 Artisia-like pith-casts occur in the Lias. Zeiller 3 has been 

 led by these facts to suppose that the Cordaitales existed 

 also in the Mesozoic. Later on he described, from the Kim- 

 meridge of Catalonia, 4 a stem without leaves but with leaf- 

 scars of the Cordaites-tyipe. Prof. Nathorst informs me, 

 however, that this stem also presents some likeness to that 

 of Wielandiella angustijolia Nath. Arber 5 has recently been 

 able to state that the fossils, previously described by him 

 as leaflets of a Cycadophyt, Zamites grandis n. sp., 6 were 

 leaves spirally arranged on a shoot. In the later paper the 

 affinities of this plant are discussed. It is recognized that 

 the material gives no satisfactory evidence on that point, 

 but, with the exclusion of the possibility of Monocotyledo- 

 nous affinities, there would be equally good grounds for an 

 attribution to the Cordaitales as to the Coniferales. The name 

 Yuccites vogesiacus Sch. & Moug. is, however, retained tempor- 

 arily. 



1 G. Compter: Die fossile Flora des untern Keupers von Ostthüringen. 

 Zeitschr. f. Naturwiss. Leipzig. Vol. 67. 1894. P. 225, pl. 4, fig. 9. 



2 O. Lignier: Végétaux fussiles de Normandie. IL Contributions å la 

 flore liasique de S te -Honorine-la-Guillaume. Mém. Soc. Linn. Normandie 

 1895. Vol. 18, p. 135, pl. 7. fig. 13. 



3 R. Zeiller: Elements de Paleobotanicjue. 1900, p. 213. 



* Sur quelques empreintes végétales du Kimméridien de Santa 



Maria de Meyä. Mem. Acad, de ciencias y artes de Barcelona. Tercera 

 época. Vol. 4. Xo 26. 1902. 



'' E. A. X. Arber: On the Affinities of the Triassic Plant Yzicciics 

 vogesiacus Schimper & Mougeot. Geo). Mag. Decade 5. Vol. 6. No 535. 

 1909, p. 11. 



On Triassic species of the genera Zamites and Pterophyllum. 



Trans. Linn. Soc. London 1907. Ser. 2. Bot. Vol. 7, Pt. 7, p. 109, pl. 17—19. 



