FOSSIL PLANTS. 
507 
rate coal basins of Western Kentucky, Illinois and Michigan with our eastern 
coal fields? The first two of these questions have been examined and answered 
in the Geological Report of Pennsylvania, pp. 839-842. Though new discove¬ 
ries might now furnish some interesting details to the discussion, nothing has 
as yet been found in the Coal Measures, which might tend to invalidate the 
conclusions admitted in that report. The third question has been also consid¬ 
ered* from data obtained in the geological explorations of Kentucky, Arkansas 
and Indiana, and therefore I have but to add here a few remarks which are 
called for by the species recently found in the Coal Measures of Illinois. 
We cannot expect to trace any marked differences indicating climatic divi¬ 
sions from the northern to the southern limits of the coal fields of Illinois. 
Local changes, as indicated from the table of distribution, can but be consid¬ 
ered as casual, and not ascribed to any permanent or general thermal influence. 
The relation of the Coal Measures of Illinois with the eastern coal fields of 
Pennsylvania, Rhode Island and Nova Scotia, is indicated not only by the com¬ 
mon or more predominant species, but also by some rare and striking ones. 
The coal of Morris, for example, has, in common with that of Newport, R. I., 
Pccopteris squamosa, Pecoptcris unita , Odontopteris Schlothcimii and Astcrophyl- 
lites lams ; with the low beds of anthracite of Pennsylvania, Callipteris Sulli- 
vantii , Neuropteris Jimbriata , N. rarinervis , N. Olarksonii, A r . Dcsorii , etc., 
and with the Coal Measures of Nova Scotia: Odontopteris subcuneata, a species 
not seen as yet in any other part of the coal fields of the United States. Some 
species of the eastern basin, like Neuropteris Rogersi, Lesqx., Odontopteris 
alata , Lesqx., Alethopteris obscura, Lesqx., Whittleseyaelegans ,Newb.,ete., have 
not yet been found in Illinois; but these are very rare species, discovered each 
at a single locality, as are some of the new species described from the coal fields 
of Illinois, and which may be found elsewhere hereafter. Illinois has likewise 
about 30 species known in the coal flora of Europe, and which have not been 
yet seen in the more eastern coal fields of America. 
Of the common species of our eastern coal fields, not yet found in Illinois, 
none can be quoted but Bictyoptcris obliqua , Bunb., locally abundant in the 
shale of the high coal near Pottsville, Penn., of Newport, R. I., and of the sub¬ 
conglomerate coal of Arkansas; Sphcnopteris artemisirefolia , Brgt., rare every¬ 
where, sparingly found in the low beds of the anthracite basin of Pennsylva¬ 
nia and of the western coal fields of Kentucky; Pccopteris arborescens , already 
quoted ; Pccopteris Losehii and the peculiar Brachyphyllum obtusum, Lesqx., 
both locally predominant in the anthracite fields. The near relation of the coal 
basin of Illinois with the other coal fields of this continent, is thus demonstra¬ 
ted by its fossil flora. 
^Journal of Science and Art, July, 1860. 
