368 BENNETTITALES [CH. 



though one species, apparently indistinguishable from those 

 referred to Mantellia, he named Bennettites portlandicus. There 

 is no adequate reason for the retention of the generic name 

 Mantellia. The close resemblance of the short and thick stems 

 (12 30 cm. in height) described by Buckland to those of some 

 recent Cycads was recognised by Robert Brown and Loddiges 

 and the former suggested to Buckland the inclusion of the fossils 

 in a new family Cycadeoideae. It was this suggestion that led 

 Buckland to adopt Cycadeoidea as a generic name. In a later 

 account of the Portland stems Buckland 1 , in deference to Brong- 

 niart's opinion, substituted Brongniart's name Cycadites for 

 Cycadeoidea. It is noteworthy that no reference is made in the 

 original description to the occurrence of lateral shoots among the 

 persistent petiole-bases that encase the Portland stems, but in 

 a later account such shoots are represented in one of the figured 

 stems and are compared with the buds occasionally produced on 

 stems of Cycas 2 . The subsequent researches of Carruthers 3 

 demonstrated the reproductive nature of precisely similar lateral 

 shoots in the stem on which he founded the genus Bennettites. 

 The generic name Echinostipes given by Pomel 4 , who had a passion 

 for instituting new nomenclature, to Buckland's Portland stems 

 has not been adopted : his genus Crossozamia proposed for certain 

 stems and fronds was revived by Carruthers 5 but has not been 

 generally used. A further complication in the nomenclature of 

 Cycadean stems was introduced by Saporta's institution 6 of 

 Bulbopodium and Cylindropodium : in the former genus he included 

 the small ovoid stem figured by Lindley and Hutton as Cyca- 

 deoidea pygmaea 7 and two French Jurassic species which might 

 reasonably be assigned to Cycadeoidea. To Cylindropodium were 

 referred some large French stems from Jurassic strata : an examina- 

 tion of the type-specimens in Paris convinced me that they are 

 typical forms of Cycadeoidea. As Ward 8 has pointed out, both 

 Saporta's genera may be merged in Cycadeoidea. Fliche and 



1 Buckland (37) p. 496, Pis. LX., LXI. 



2 Ibid. (28), PI. LXI. fig. 1. A specimen in the Oxford Museum may be the 

 original of Buckland's figure. 



3 Carruthers (70). 4 Pomel (49) p. 16. 6 Carruthers (70) p. 690. 



6 Saporta (75) A. pp. 256, 265, Pis. 118, 119. 



7 Lindley and Plutton (35) A. PI. 143. 8 Ward (94). 



