XXXIX] SPHENOZAMITES 587 



with also in Ctenis sulcicaulis. This description is based on an 

 examination of the specimens figured by Feistmantel. 



III. CYCADEAN FRONDS WHICH CANNOT BE ASSIGNED TO A 



FAMILY-POSITION. 



SPHENOZAMITES. Brongniart. 



This name was proposed by Brongniart 1 as a subgenus of 

 Otozamiles denoting pinnate fronds bearing leaflets without an 

 auriculate base : he suggested that the subgenus might eventually 

 be raised to generic rank and this was done by Zigno 2 though in 

 too wide a sense. In the case of Otozamites Beani (Lind. and 

 Hutt.), quoted by Brongniart in illustration of Sphenozamites, 

 the latter designation is inapplicable as the pinnae are auriculate. 

 Another species, Zamites undulatus Sternb., to which Brongniart 

 applied his new subgeneric term, is probably identical with 

 Otozamites acuminatus (L. and H.) 3 . 



Although the distinction between Sphenozamites and Oto- 

 zamites is often ill defined the former name may be conveniently 

 adopted for pinnate fronds similar to those of Zamia Skinneri 

 and some species of Encephalartos characterised by leaflets of 

 an asymmetrical, obovate, or rhomboidal form with a contracted 

 or cuneate base and numerous branched divergent veins. Nothing 

 is known of the structure or reproductive organs of Sphenozamites, 

 and the genus, though serving a useful descriptive purpose, is 

 founded solely on form, and in the absence of other data it would 

 be rash to assume that its use implies close natural affinity. In 

 the case of many other genera of Cycadean fronds there is addi- 

 tional evidence of relationship, but this is not the case with 

 Sphenozamites. The pinnae resemble those of such recent Cyca- 

 dean fronds as Zamia Skinneri and Z. muricata. The genus 

 ranges from Lower Permian to Jurassic rocks. 



Sphenozamites Rochei Renault. 



This species 4 , from the Lower Permian of the Autun district, 

 is founded on a pinnate frond bearing alternate pinnae, 2-5 x 1 cm., 

 with an asymmetrical oblong lamina attached obliquely near 



1 Brongniart (49) A. p. 61. 2 Zigno (85) p. 105. 



3 Seward (00) B. p. 215. 



4 Renault (96) A. p. 327; (93) A. PI. LXXXI. fig.,1. 



