FOSSIL PLANTS. 491 



The shale of the coal at Morris and the concretions of Mazon creek have 

 furnished also a number of specimens of three species, or rather forms, of 

 Paloeoxyris, a kind of organism which is considered by Brongniart, Schimper, 

 and other naturalists, as a plant belonging to a higher class of the vegetable 

 kingdom, that of the monocotyledbnousphoenogomous plants. In describing these 

 bodies, I have expressed my views on their nature. If the opinions of the Eu- 

 ropean authors are right, we have already, from the lower part of the Coal 

 Measures of Illinois, vegetable organisms of a class of plants, whose first ap- 

 pearance has been marked in the Triassic period. Though it may only effect 

 their generic affinity, the presence of these bodies in the concretions of Mazon 

 creek is the more remarkable that they are there associated, as in the Permian 

 of Europe, with a quantity of animal remains, especially insects of large size, 

 which have, as yet, not been discovered elsewhere in the Carboniferous for- 

 mations. 



There has been found in the Coal Measures of England and Nova Scotia, 

 specimens of fossil wood, referable by their tissue, a compound of large woody 

 cells or fibres, marked by vertical circular spots, to the Conifers or Pine family. 

 It is remarkable that most of the fossil wood of our Devonian strata indicates 

 the same characteristic form of cells, and that as yet, neither in Illinois nor in 

 other parts of our true Coal Measures, no kind of branches, leaves, or petrified 

 wood distinctly related to this order of vegetables, have ever been observed. 

 The fragments described from a nodule of Mazon creek in vol. 2, p. 447, pi. 

 xxxvii, fig. 3, of this Report, under the name of Lycopodites asterophyllitsefo- 

 lius, resembles, indeed, a branch of some kind of Conifer, but it is as well com- 

 parable to some species of Lycopodiacese. We have also obtained from the 

 lower strata of the Coal Measures of Illinois and of Pennsylvania, specimens 

 of Artisia transversa, Sternb., a species whose affinity is still uncertain, it being 

 considered by Dawson a Conifer, while most of the European palaeontologists 

 describe it with the Lycopodiacese. Our specimens are all transformed into 

 sandstone, with no other part preserved but the mold, do not afford any light 

 on this question. From this uncertainty as to the true affinity of these vege- 

 table remains, and what is said above concerning other orders of fossil plants 

 found in the Carboniferous strata, it would seem proper to conclude that the 

 flora which has furnished the materials for the formation of our coal, and which 

 covered the bogs of our continent at the Carboniferous epoch, was limited to a 

 single group of vegetables, that of the acrogenous cryptogams. (1) The same 



(1) Prof. Goppert considers the genus Sigillaria as rather related to a gymnosperm family. 

 Its relation with the genus Lfpidodendron is too evident to permit this conclusion ; the cones 

 and seeds of Sigillaria have moreover been found in our Coal Measures, of the same charac- 

 ter as those described by Goldenberg. 



