206 SPHEXOLEPIDIUM. 



pi. ii. fig. x. seems to be identical with what he called Widdring- 

 tonites Haidingeri, and which we have included, following Schenk's 

 example, as a synonym of 8. Sternbergianum, Most of the speci- 

 mens figured by Ettingshausen as Araucarites curvifolius (Dunk.), 

 must no doubt be included in the present species, and are not 

 identical with Dunker's Lycopodites curvifolius. Some of the 

 species, on the other hand, are the same as Dunker's type, 

 and do not appear to belong to Splienolepidium Sternbergianum. 

 Fontaine's small specimens agree with this species, but it is 

 impossible to discriminate with any degree of certainty between 

 the numerous and very similar twigs, which he figures from the 

 Potomac beds under different specific names. 



If we compare the figures of Sequoia ambigua, Heer, 1 with 

 SpJienolepidium Sternbergianum (Dunk.), we find a striking re- 

 semblance ; e.g., Heer, pi. xxi. fig. 3, and Schenk, pi. xvi. 

 figs. 3 and 4. It is exceedingly difficult to come to any satis- 

 factory conclusion as to the specific identity of these various 

 coniferous twigs ; and the striking resemblance between the 

 branches of certain recent forms, should sufficiently demonstrate 

 the futility of attempting to carry our comparisons too far in 

 the case of fossil fragments. It would seem, however, that if 

 Heer's Greenland plant is not identical with the present species, 

 it is closely allied to it. S. Sternbergianum differs from the 

 preceding species chiefly in the more open and linear leaves. 

 As regards the cones of the two species, it is not quite clear how 

 far Schenk's description of a specific difference holds good ; the 

 material from the English beds is hardly sufficiently well preserved 

 to enable us to give any satisfactory detailed diagnosis. 



V. 2311. PL XVI. Fig. 4. 



An imperfectly preserved specimen showing two cones attached 

 to short branches. The difference in the leaf form from that of 

 S. Kurrianum is clearly shown. Ecclesbourne. Rufford Coll. 



V. 2144. PI. XVI. Fig. 6. 



Well-preserved branches with spreading and falcate leaves. 

 Ecclesbourne. Rufford Coll. 



1 Heer, Fl. foss. Arct. vol. iii. (2) pi. xxi. etc. 



