BY THE REV. J. E. TENISON-WOODS, F.G.S., F.L.S. 69 



their whole extent, and the free ends are obtusely pointed, rounded 

 or even flat ; but this may depend on the state of preservation of 

 the specimens, for none of the fragments were well preserved. The 

 color of the fossils being so near to that of the shale, made it more 

 than usually difficult to determine the more delicate details of 

 structure. 



From all the specimens I have seen, I cannot come to any other 

 conclusion than that the stems were smooth and not fluted in any 

 way, except on the outside of the spathe or sheath above the 

 diaphragm, where the separate teeth make divisions or grooving. 



Other parts of this plant, such as the rhizome, roots and 

 fructifications have not been found with certainty, and therefore 

 no well-founded comparison can be made. It is very near to 

 E. rajmahalensis, which is also considered to be closely allied to 

 E. miinsteri, Stbg. In this species, the stem does not seem to be 

 fluted in some specimens, but there is a manifest difference in the 

 diaphragmata, and the teeth of the spathe are keeled, which is not 

 the case in our fossil. E. miinsteri, is now recognized as identical 

 with many subsequently named species, such as E. moniliformis 

 Prsl., E. alternatus, Prsl, Catamites liaso-keuperiamis, Braun. 

 It is very common in the Rhsetic strata of Europe, but also ascends 

 into the Lias. E. rajmahalensis, is referred by Feistmantel to the 

 Liassic period. 



In the rocks of the same period of Europe we have, E. 

 gamingianum Etting., and E. ungeri, Etting., both of which have 

 smooth stems, but the first has very narrow teeth, and the second 

 has them, though broad, produced into a long rigid subulate point. 

 I do not think it necessary to institute any other comparisons, 

 with such species such as E. arenaceum, as they diverge widely from 

 our type, 



Phyllotheca Brongt. 



In the same family of Equisetacece, is placed the genus 

 Phyllotheca, which is distinguished from Equisetum by the sheath 

 being prolonged into long linear leaves. The distinction may be 

 better borne in mind by the following table. 



