the older genus _Cycadeoidea_: one such type from the Portlandian of Boulogne is described by these authors as _Cycadeoidea pumila_. Saporta also proposed the name _Platylepis_[1087], the type-species being _Cycadeoidea micromyela_ Mor., from the Lias of Calvados, which has recently been investigated by Lignier[1088] who wisely adopts Morière’s designation. Another unnecessary generic name is _Schizopodium_ given by Morière to a stem, _S. Renaulti_[1089], regarded by Lignier as indistinguishable specifically from _C. micromyela_. The two names _Cycadeoidea_ and _Bennettites_ have been used by authors for stems which are unquestionably generically identical and as is often the case much confusion has been caused through the failure of palaeobotanists to arrive at an agreement. Lester Ward, a staunch advocate of the rule of priority, repeatedly pointed out that Buckland’s name _Cycadeoidea_ should take precedence of _Bennettites_ on the ground that stems for which these genera were instituted are clearly of the same type, and he added that the older genus, though abandoned by its author, cannot be given up without violating the inexorable rules of priority. On the other hand it has been urged that the genus _Bennettites_ as defined by Carruthers is characterised by the possession of (i) fertile shoots bearing strobili and (ii) vegetative organs exhibiting certain anatomical characters. Buckland’s species of _Cycadeoidea_, though bearing lateral shoots, are not well enough preserved to afford definite information as to the morphological features of the strobili, nor have we satisfactory data with regard to the degree of resemblance between the vegetative features of _Bennettites_ and the Portland stems. Carruthers laid stress on the elliptical section of the stele in _Bennettites_ in contrast to the cylindrical cylinder of Buckland’s _Cycadeoidea_ trunks. Subsequent research has shown that this difference is not in itself a valid criterion either of generic or specific rank but, as Wieland says, it is an open question to what extent the stem structure of _Cycadeoidea_ and _Bennettites_ agrees. The probability is that were our knowledge of the Portland stems less incomplete, they would be found to possess no anatomical features inconsistent with this generic union. Granting the correctness of this view, the adoption of the later generic term would be a reasonable course to follow on the ground that it stands for stems showing well preserved structure, while _Cycadeoidea_ was in the first instance applied to stems showing only partially preserved stumps of strobili, and the name was not retained by its author. Graf Solms-Laubach[1090] and some other authors have used _Bennettites_ for Cycadean stems possessing strobili of known structure such as those of _Bennettites Gibsonianus_, reserving _Cycadeoidea_ for similar stems but without strobili sufficiently well preserved to afford evidence of morphological characters.