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#' " PRB-CARBONIFBROUS PLANTS. 19 



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microscope ; but in this condition the pores present a mere reticulation 

 •without any appearance of proper discs. When portions containing pyrites 

 are submitted to the action of dilute hydrochloric acid, the pyritized parts 

 remain and can be separated. These, seen under the microscope as opaque 

 objects, often show the most beautiful casts of the fibres, exhibiting the 

 discs in great perfection on their surfaces. As is often the case with other 

 fossil woods, imperfectly preserved specimens show a tendency to radia- 

 ting crystalline structures which are often curiously complicated with the 

 radiating cracks following the medullary rays and the concentric lines of 

 growth. Fig. 1 shows a specimen of this kind as seen in a polished trans- 

 verse section. 



More recently, the oflScers of the Geological Survey have collected at 

 Lepreau, New Brunswick, additional specimens of this species, differing 

 somewhat in their state of preservation from those at St. John. They are 

 compressed and silicified, and shew the more minute structures of the 

 woody fibres even more perfectly than the specimens previously in my 

 possession. They exhibit the peculiar oblique arrangement of the pores 

 which is also seen in some Carboniferous species, as well as in the wood 

 of some Sigillarise, and in the modern world is observed in Cycads and in 

 Taxine conifers. They also show, better than my former specimens, the 

 medullary rays, composed of from one to three series of cells, and with as 

 many as fourteen cells sometimes superimposed on each other. It will be 

 observed that this species thus occupies a position intermediate between the 

 ordinary species of Dadoxylon, and those with several series of cells in 

 the medullary rays, which Brongniart has separated to form his genus 

 I^alceoxylon. 



No specimens which can be certainly regarded as the foliage or fruit 

 of this species have been found. The specimens all appear to be drifted 

 trunks, and the largest hitherto found, in so far as I am aware, was twelve 

 inches in diameter. This specimen was collected by Mr. Matthew, and 

 was stated to have had a cast of a Sternbergia pith no less than two and a 

 half inches in diameter. Judging from the analogy of recent plants, this 

 great diameter of the pith would indicate that the branches must have 

 been few and thick, unless indeed we suppose that this feature was limited 

 to the main stem, and that small branches of different structure have 

 sprung in whorls from its sides. 



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