78 Mr. Thomas Hick on a Sporangiferous Spike 



of Bowmanites Dawsoni* Subsequently, Zeiller came to 

 the conclusion! that it was identical with the fruit-spike 

 described by him as that of Sphenophyllum cuneifolium,, 

 and this conclusion has been adopted by Williamson and 

 Scott, except as regards the specific identity of the two.j 



Now, in this type of Sphenophyllum fruit, sporangio- 

 phores are present, but they are very different structures 

 from those met with in the Calamariece. They are SO' 

 delicate indeed, and are attached to the bracts and 

 sporangia in such a way, that if other types have similar 

 characteristics one need not wonder that impressions of 

 the fruit-spikes of Sphenophyllum afford few or no traces 

 of them. In any case, in the absence of distinguishable 

 sporangiophores, though it is but a negative agreement, we 

 have one point in which the Rochdale spike agrees with 

 those of Sphenophyllum. 



Figures and descriptions of the spikes of Sphenophyllum ,. 

 as seen in impressions, are given by both Renault § and 

 Zeiller || among recent writers on the subject. Com- 

 paring our specimen with these, there is certainly a 

 strong general resemblance between them, though some- 

 differences of detail are also met with. According to 

 Renault IT the sporangia of Sphenophyllum are always, 

 placed between the bracts but at the same level, or else, 

 they are inserted upon the upper surface of the same. In 

 our specimen, the sporangia appear to be upon the upper 

 surface of the bracts, so that there is agreement on this 

 point, as there is also in the shape of the sporangia and 

 their position with the long axes more or less vertical. 

 Among the published figures to which the spike bears 

 some resemblance, reference may be made to those given 

 by Zeiller of the fruit-spike of what he names Spheno- 



* Phil Trans., 1890 and 1891. f Comptes renins, 1892. 



% Phil. Trans., 1895. § Cours de Botaniquc fossile, 2« Anna, 1882^ 



|| Flore fossile de Valenciennes, 1888. ^[ Loc. cit., p. 86. 



