XLV] VOLTZIA 291 



lum. Schiitze 1 has given a long list of references to records of 

 F. heterophylla. but in making use of such lists it should be remem- 

 bered that in the absence of reproductive organs the specific or 

 even generic determination of specimens resembling in habit 

 Araucaria excelsa is a hopeless task. The heterophylly of Voltzia 

 heterophylla is a striking feature : long linear obtuse leaves, 2 5 

 cm. long, occur in close association with falcate decurrent foliage. 

 Small oval strobili characterised by crowded imbricate appendages 

 are figured by Schimper and Mougeot as male cones, but in no case 

 have any sporangia been detected : similar strobili are also figured 

 by Leuthardt 2 from the Keuper of the Basel district. The mega- 

 strobili are longer and bear cuneate cone-scales, with 3 5 rounded 

 lobes on the upper surface, arranged in a lax spiral. The marginal 

 lobes of the scales are less deeply separated from one another 

 than in F. Liebeana (fig. 748, D F). We have no satisfactory 

 information with regard to the nature or method of attachment 

 of the seeds. Saporta 3 figures a cone from Soultz-les-Bains 

 showing, as he asserts, the impressions of seeds, but the drawing 

 affords no definite evidence as to the relation of cone-scales and 

 seeds. Saporta regards the cone-scales as double, each consisting 

 of an ovuliferous scale and a bract-scale more or less completely 

 fused as in the recent genus Taxodium. The assumption that the 

 scales are double rests on a very slender basis, and even in the 

 much better preserved specimens of F. Liebeana ' there is nothing 

 to indicate that the scale was double 4 .' In a recent paper Miss 

 Holden 5 speaks of Voltzia cone-scales as double in terms suggesting 

 a well-established fact, though this is by no means the case. 



Blanckenhorn 6 and other authors have described specimens of 

 Voltzia heterophylla showing elongated leaf-cushions which they 

 compare with similar raised areas on the Permian casts on which 

 Weiss founded the genus Tylodendron (Schizodendron 7 ). In the 

 latter genus the supposed leaf-cushions are casts of medullary 

 rays at the inner edge of the secondary xylem, and an examinatioir 

 of Voltzia specimens in the Strassburg Museum 8 convinced me that 



1 Schiitze (01). 2 Leuthardt (03) p. 10, PL iv. 



3 Saporta (84) PI. 154, fig. 4. 4 Solms-Laubach (91) A. p. 68. 



5 Holden, R. (13) p. 251. 



6 Blanckenhorn (85) B. PL xx. figs. 1720. 



7 See page 282. 8 Seward (90). 



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