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THE POPULAR SCIENCE MONTHLY. 



ranged in concentric zones, which, if annual rings, would in some 

 specimens indicate an age of one hundred and fifty years. There are 

 also radiating spaces, which I was at first disposed to regard as true 

 medullary rays, or which at least indicate a radiating arrangement of 

 the tissue. They now seem to be spaces extending from the center 

 toward the circumference of the stem, and to have contained bundles 

 of tubes gathered from the general tissue and extending outward per- 

 ha])S to organs or appendages on the surface. That the jjlant grew on 

 land I can not doubt, from its mode of occurrence ; that it was of 

 durable and resisting character is shown by its state of preservation ; 

 and the structure of the seeds called Fachythcca, with their constant 

 association with these trees, give countenance to the belief that they 

 are the fruit of Nematophyton. Of the foliage or fronds of these 



KiQ. A.—Nematopliytcn Logani (maKiiifii'dl- Kestoratioii.* 



Strange plants we unfortunately know nothing. They seem, however, 

 to realize the idea of arboreal plants having structures akin to those 

 of thallophytes, but with seeds so large and complex that they can 

 scarcely be regarded as mere spores. 



Multitudes of markings occurring on the surfaces of tiie older 

 rocks have been referred to the algie or sea-weeds, and indeed this 

 group has been a sort of refuge for the destitute to which paleontolo- 

 gists have been accustomed to refer any anomalous or inexplicable 

 form which, while probably organic, could not be definitely referred 

 * Figs. 2, 3, and 4 are drawn from nature, by Professor Penhallow, of MeGill College. 



