3IO 



HOMER G. TURNER AND H. R. RANDALL 



Fig. I. — (X170) crosswise to the bed- 

 ding, from Pennsylvania anthracite. 

 Shows spore exines. The markings on the 

 spores are probably lines of dehiscence. 

 This group of spore exines was found in 

 the duller layers. 



Fig. 2. — Section (X170) crosswise to the 

 bedding, from Pennsylvania anthracite. 

 Shows large, wrinkled spore exines found in 

 the duller layers. 







Fig. 3. — Section (X125) crosswise to the 

 bedding, from Pennsylvania anthracite, 

 showing crushed and warped cells, ob- 

 served in a zone surroimding a knot of 

 almost structureless charcoal. 



possess a more perfect con- 

 choidal fracture. Where they 

 are thick, the broken surface 

 often shows rounded or oval 

 fracture forms. Although the 

 above distinctions hold true for 

 most of the anthracite, some 

 varieties appear at first glance 

 to be composed wholly of the 

 briUiant coal, revealing their 

 various laminae only on careful 

 examination. 



Mineral charcoal was quite 

 abundant in almost all the coal 

 examined. Cleaving coal par- 

 allel to the bedding exposed 

 charcoal-covered surfaces in 

 every specimen which showed 

 distinct lamination. On the 

 other hand the varieties 

 which were poorly laminated 

 and almost uniform in luster 

 contained very little charcoal. 



In addition to the thin sheets 

 of charcoal so commonly found 

 in the bedding planes, one 

 finds occasional large fragments 

 which cross several of the hori- 

 zontal layers. These large 

 pieces of charcoal are of par- 

 ticular interest because of the 

 fact that they show in most 

 cases perfect cells almost en- 

 tirely devoid of filling. The cell 

 walls are thicker than those of 

 the original wood and appear to 

 be lined with a bright jet black 

 layer which permits good pho- 

 tographs by reflected light. All 



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