XXXIX] ZAMITES 529 



guard-cells show no cuticularised bands. In habit this species 

 resembles Encephalartos Ghellinckii Lehm. (fig. 382). The super- 

 ficial resemblance of the narrow linear pinnae to those of Cycadites 

 led Dunker and Schenk to refer to that genus some specimens 

 which have since been described as identical with P. Dunkerianum. 



ZAMITES. Brongniart. 



In the first instance the generic name Zamites was used in 

 addition to Zamia for certain pinnate fronds including species 1 , 

 such as Z. Bechei, which are now regarded as typical examples 

 of Otozamites. Subsequently Brongniart gave up Zamia for 

 fossil fronds and applied Zamites to fronds with entire pinnae, 

 not truncate at the apex and not decurrent but slightly constricted 

 at the base. Braun's two genera Podozamites and Pterozamites 

 were relegated to the position of subgenera. The name Podo- 

 zamites has been employed by Schenk 2 for specimens now included 

 in Zamites, and Zamites is used by him 3 for some fossils which are 

 examples of Podozamites as generally understood. Goeppert's 

 definition 4 of Zamites includes fronds with pinnae of the Otozamites 

 type, and this author pertinently compares Zamites with recent 

 Encephalartos leaves. Pomel 5 proposed the name Crossozamia 

 for certain fronds of the Zamites type, but this genus with several 

 others instituted by the same author has not been adopted. 

 Bornemann 6 described Zamites as comprising species with a greater 

 or less resemblance to the fronds of recent Zamias. 



As defined below, Zamites fronds may be compared with those 

 of some species of Encephalartos, Ceratozamia, and Macrozamia. 

 There has been considerable difference of opinion with regard 

 to the range of form in the pinnae that it is advisable to include 

 in Zamites. The name Zamiophyllum was proposed by Nathorst 7 

 for a Wealden species, described by Ettingshausen as Pterophyllum 

 Buchianum (fig. 601, A C), characterised by a decrease in the 

 breadth of the linear pinnae towards the point of attachment 

 and, according to Nathorst' s description, by the lateral attach- 

 ment of the pinnae. An examination of specimens of this type 



1 Brongniart (28) A. p. 94. 2 Schenk (71) B. p. 8. 



3 Schenk (67) A. Pis. xxxvi. vn. 4 Goeppert (44) p. 122. 



6 Pomel (47) p. 342. 6 Bornemann (56) A. p. 54. 



7 Nathorst (90) A. p. 46. 



s. in 34 



