AN UNDESCKIBEI) I'OSSIL I'lUIT. ."iSO 



is Lycopodiacece, The same view is in great part adopted 

 in my pa[)er. But I hesitated in absolutely referring 

 Irijjlosjjorile to Lq)ido8trobu>^, from the very imperfect know- 

 ledge then ])osscssed of tlie structure of that genus. The 

 speeimeiisofZ(7;<!V/6'.s7r6'/^/A' examined ])y M. Ih'ongniart were 

 so incomplete, that they suggested to him an erroneous view 

 of the relation of the supposed sporangium to its supporting 

 bractea, and of the contents of the sporangium itself they 

 afforded him no information whatever. 



In concluding my account of TriplosporUc, I noticed the 

 then very recent discovery of spores in an admitted species 

 oi Lqndostrohis by Dr. Joseph IJooker, who, aware of the 

 interest I took in everything relating to Triphsporitc, the 

 sections and drawings of wliich he had seen, communicated 

 to me a section of the specimen in which spores had been ob- 

 served, but which in other respects was so nmcli altered by 

 decomposition, that it afforded no satisfactory evidence of the 

 mutual relation of the parts of the strobilus. The appear- 

 ances, however, were such, that I hazarded the opinion of its 

 being generically different from IVipIosporifc, an opinion 

 strengtheued by j\I. Erongniart's accouut of the origin of 

 the sporangium. 



Since the abstract of my paper was printed in the Pro- ir. 

 ceedings of the Society, the second volume of the Memoirs 

 of the Geological Survey of Great Britain has appeared, 

 which contains an article entitled '' Remarks on the Struc- 

 ture and Affinities of some Lrpidostrobl'' The principal 

 object of Dr. Hooker, the author of this valuable essay, is 

 from a careful examination of a number of specimens, all 

 more or less incomplete, or in various degrees of decompo- 

 sition and consequent displacement or absolute abstraction 

 of parts, to ascertain the com])lete structure or connuon 

 type of the genus Lcpldos/rohus ; but the type so deduced 

 is in every essential point manifestly exhibited, and in a 

 much more satisfactory manner, by the single specimen of 

 Triplosporife. This does not lessen the value of Dr. 

 Hooker's discovery and investigation, but it gives rise to the 

 cpiestion whether Trijilosporilc, which he has not at all 

 referred to, and therefore probably considered as not belong- 



