L] PALISSYA 427 



has been employed by several authors for Mesozoic shoots with 

 linear leaves unaccompanied by reproductive organs and having 

 therefore no claim to be assigned to a genus characterised by a 

 well denned type of strobilus. Further reference to the mis- 

 application of Palissya is made in the account of some Indian 

 specimens recently assigned to Retinosporites. In the absence of 

 any evidence of the occurrence of strobili, shoots similar in habit 

 to Palissya should be described under Halle's generic name 

 Elatocladus. An impression of a shoot from Triassic beds in 

 Bucks County, Pennsylvania, recently described by Wherry 1 as 

 Palissya longifolia, would be more appropriately referred to Elato- 

 cladus as it affords no indication of the nature of the fertile branches. 



Palissya sphenolepis (Braun). 



Nathorst 2 in his recent and able account of this species reverts 

 to the older specific name on the ground that Endlicher's name 

 P. Braunii is not in accordance with the laws of priority. It is 

 possible though not certain that some specimens described under 

 different names by Presl prior to the publication of Braun's account 

 of Cunninghamites sphenolepis may belong to this species. Schenk 

 considerably extended Braun's description and was the first to 

 publish figures of ripe cones showing certain morphological features 

 of the seed-bearing scales which authors have differently interpreted. 

 Palissya sphenolepis is a Rhaetic species recorded from Franconia 

 and Scania, possibly more closely allied to the genus Cunninghamia 

 than to any other existing Conifer; but, as Nathorst suggests, it 

 may belong to an extinct section of Gymnosperms. The foliage- 

 shoots bear spirally disposed, two-ranked, leaves of the Taxites 

 form; the lamina is narrow and linear with a median vein, decurrent 

 on the axis as a persistent leaf-cushion. The epidermal cells have 

 straight walls and the stomata, confined to the lower surface, occur 

 in two rows. Palissya cannot be identified with any degree of 

 certainty in the absence of well-preserved strobili. The mega- 

 strobili are cylindrical and relatively narrow ; in an immature con- 

 dition they closely resemble those of Elatides, the surface being 

 formed of the lanceolate, imbricate, distal ends of crowded cone- 

 scales. It is the older strobili with elongated internodes that 



1 Wherry (16). 2 Nathorst (08 2 ). 



