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Remarks on the Structure and Affinities of some Lepibostrobi. By 

 Dr. Hooker, F.R.S., &c, Botanist to the Geological Survey of the 

 United Kingdom. 



The numerous detached petrified cones which are scattered through 

 the various strata of the coal formation, being obviously organs of fructi- 

 fication, and having therefore belonged to some of the arborescent 

 plants whose remains they accompany, are objects of peculiar inte- 

 rest to the fossil-botanist and geologist. Such of them as are preserved 

 in the nodules of iron-stone, or are otherwise mineralized without pres- 

 sure, alone offer the means of ascertaining to what existing families of 

 plants they are most nearly allied ; for in those that are crushed flat 

 in the shales the internal structure is wholly destroyed. Many of the 

 better preserved specimens have been sliced, polished and examined 

 with the greatest care ; but this expensive operation has hitherto thrown 

 little light upon the true nature of the objects thus investigated. 



This is because the three following conditions for their complete 

 illustration has never been displayed by one specimen, and the most 

 important point — the nature of the organs of fructification — has 

 hitherto wholly escaped observation in all. Every cone being an 

 aggregation of organs of some kind, it becomes necessary to ascertain 

 not only the arrangement of these organs, but the nature of the tissues 

 composing them, and (even more essential) their contents, before satis- 

 factory conclusions can be drawn as to their relationship to any of the 

 vegetable remains they accompany, or to whatever existing order of 

 plants they are allied : — 



1. The arrangement of the individual organs of fructification, of 

 which the cone is an aggregation, and the nature of the scales support- 

 ing them. These are characters sometimes displayed on the fracture 

 of the specimen by ordinary means, though rarely, from the parts ap- 

 pearing to have suffered partial decay previous to or during petrifac- 

 tion. The imbricating apices of the scales, which lie over one another 

 like those of a pine-cone, are generally removed with the matrix 

 wherein the fossil is imbedded, as is seen by contrasting plate 8, fig. 1, 

 with fig. 3, in the former of which the apices of the scales have per- 

 sisted, whilst in the latter they are uniformly broken away. The muti- 

 lated is the more usual state of the surface, for reasons which shall be 

 afterwards detailed. 



2. The tissues, or anatomical structure of the various organs com- 

 posing the cone ; viz., of the central axis, which is a continuation of the 



