122 



BUCKLANDIA. 



of the English fossils. In the Tableau 1 Brongniart includes Mantell's 

 plant in the Liliacece, noting at the same time its resemblance to 

 the stem of a cycad. Schimper 2 retains Clathraria for plants of 

 the type of Clathraria anomala, Stokes and Webb (C. Lyelli, 

 Mant.); and Saporta, 3 who follows Carruthers in preferring the 

 name Bucklandia to Clathraria, speaks of the plant figured by 

 Schenk as C. Lyelli as probably a species of Carruthers' genus 

 Fittonia. JSathorst, in his Floran vid Bjuff on the other hand, 

 includes under Clathraria two new species, but in the latter part 

 of the same work he substitutes Bucklandia 5 for Stokes and 

 Webb's genus. Nathorst's specimens are imperfect fragments 

 of stems with alternating series of narrower and crowded leaf- 

 scars, and broader and more openly arranged leaf bases; he 

 compares them with the stem of Cycas. 



The separation of such conventional genera as Bucklandia and 

 those proposed by Saporta, is often a matter of great difficulty, 

 and so long as we have only imperfect external or internal casts 

 to deal with, there must always be a certain amount of doubt 

 as to the existence of true generic and specific differences. 

 Carruthers thus defines the genus Bucklandia : 



"Trunk cylindrical, sometimes bifurcating, reticulate, with the 

 scars of the bases of the leaves, which are arranged in alternating 

 series of large and small scars, the large being placed on swellings 

 and the small on constrictions of the stems. Andrcecium a cone (?), 

 gyncecium a terminal crown of leaves bearing seeds on their some- 

 what altered margins." 6 



The so-called male cone referred to in this definition was 

 discovered in the same series of strata as those in which 

 Bucklandia occurs ; it is assigned to this genus on the strength 

 of its occurrence in the same beds, and on account of a resemblance 

 which its scales present to the sporophylls of a male flower of 

 the recent species of Cycas. In the absence of more satisfactory 

 evidence than is afforded by this single imperfect specimen, the 

 nature of which does not appear to be by any means established, 

 we are not in a position to include the male flower in a definition 

 of Presl's genus. The alternating swellings and constrictions 



1 Brongniart (A. 4), p. 91. 4 Nathorst (A. 1), p. 77. 



2 Trait, pal. veg. vol. ii. p. 182. 6 Ibid. p. 124. 



;i Loc. cit. p. 307. 6 Loc. cit. p. 682. 



