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Dr. J. W. Dawson on Spore-cases in Coals. 



land. Goeppert mentioned and figured them in his ' Treatise 

 on Coal ' in 1848. Balfour described them in 1859 as occur- 

 ring in Scottish coals ; and Quekett figured them in his account 

 of the Torbane-Hill mineral in the same year. In 1855, the 

 latter microscopist showed me in London slices exhibiting 

 round bodies of this kind, very similar to those now described 

 by Huxley ; but at that time I regarded them as concretionary, 

 though Prof. Quekett was disposed to consider them organic. 

 Mr. Carruthers has summed up most of these facts in his ac- 

 coimt of his genus Flemingites in the '■ Geological Magazine ' 

 for October 1865. The subject has also attracted the attention 

 of microscopists in connexion with the Tasmanite or " white 

 coal" of Tasmania, which is composed in great part of the 

 spore-cases of ferns. 



I suppose that the oldest spore-cases known are those de- 

 scribed by Hooker from the Ludlow formation of the Upper 

 Silm-ian ; but these, if really spore-cases, are different in 

 structure from those ordinarily found in the coal-formation, 

 more especially in the great thickness of their walls, and I am 

 not aware that they have anywhere been found in considerable 

 quantities. 



The oldest bed of spore-cases known to me is that at Kettle 

 Point, Lake Huron. It is a bed of brown bituminous shale, 

 bm-ning with much flame, and, under a lens, is seen to be 

 studded with flattened disk-like bodies, scarcely more than a 

 hundredth of an inch in diameter, which mider the microscope 

 are found to be spore-cases, slightly papillate externally, and 

 with a 25oint of attachment on one side and a slit more or less 

 elongated and gaping on the other (figs. 1,2,3). I have proposed 



Fig. 1. Part of a slice of shale from Kettle I'l.int, showing two spore- 

 cases and remains of spores. Magn. 70 diams. 

 Figs. 2 & 3, Spore-ca.ses from the same, as opaque objects. 70 diams. 



