A PALEOZOIC ANGIOSPERM 



A. C. NOfi 

 University of Chicago 



The morphology of Paleozoic plants is based for the most part 

 upon the microscopic examination of concretions found in English, 

 French, and German coal seams. These concretions are calcareous 

 in England, and siliceous in France and Germany, and contain 

 well-preserved tissues of plants. The matrix can be cut with a 

 diamond saw, and the sections ground to transparency. The 

 concretions are black, round, or irregular lumps, varying in size 

 from an English walnut to a cocoanut. They appear in the upper 

 part of the coal seam but never outside of it. In England they are 

 called coal-balls and in Germany Torfdolomiten. The French use 

 the English word. The value of a coal-ball for morphologic plant 

 study depends not only upon the vegetable contents but also upon 

 its purity from pyrite. The latter does little harm if it occurs in 

 very small quantities, but observations are made impossible if the 

 replacement of calcite or silica has progressed too far. 



A great service to science, in making micropreparations from 

 English coal-balls, has been rendered by the Lancashire and Ceshire 

 Coal Research Association, better known as the Lomax Palaeo- 

 Botanical laboratories of Bolton, England. There a wonderful 

 technique has been developed by Mr. Joseph R. Lomax, who pre- 

 pared the material for the classic investigations of W. C. Williamson, 

 D. H. Scott, A. C. Seward, R. Kidston, F. W. Oliver, A. J. Maslen, 

 and M. Benson. Almost all paleobotanic micropreparations in 

 England and North America were supplied by the Lomax labora- 

 tories. 



It seemed obvious that coal-balls should also be found in the 

 extensive American coal basins, and a thorough search was made 

 for them. The writer has collected good specimens in Illinois and 

 Kentucky, and others were sent to him from Texas. It is true that 



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