528 PALiEONTOLOGlCAL REPORT OF GEOLOGICAL SURVEY. 



monds, peanuts, or peas.* The ferns imbedded in the shales are gen- 

 erally of the largest species. The genus Sphenopieris, (pi. 6, fig. 1,) 

 is represented in this low coal by most of its species, which are scarce- 

 ly found above it, and some large Teeopteris, especially Tecopteris lon- 

 cMtica, (pi. 6, fig. 3,) belong also to this bed only. Neuropteris her' 

 suta, &c, (pi. 6, fig. 4,) is generally found in the shales; but this 

 plant appears in the whole thickness of the Coal Measures, as well in 

 Europe as in America. We mention it only to prevent mistaking it 

 as the characteristic plant of a certain level, or admitting, for peculiar 

 species, the numerous forms of its curious leaves scarcely ever found 

 attached to the stems. These leaves are ordinarily Janceolate-oval, 

 with a heart-shaped base, and have two small round kidney-shaped 

 leaflets attached at its base, but sometimes they become either large, 

 and nearly round, (Ci/clopteris,) or narrow lance-shaped, or palmately 

 cut in two or three linear divisions. Since its surface is ordinarily 

 strewn with scattered hairs, all these forms can easily be referred to 

 their species. 



It has been asserted by many that Stigmari a ficoides, (pi. 7, figs. "2 

 and 2a,) is a plant, or rather a root, found in the fire-clay only, where it 

 has sprung, supporting the trees that have formed the coal above it. 

 This is a great mistake, which would be corrected by a single look at 

 our bed, No. 1 coal, where the coal itself, and the shales above it, con- 

 tain most abundant specimens of those Stigmaria. 



A remarkable peculiarity of the black shales of this coal is, that 

 they contain, also, in immense numbers, the remains of a single spe- 

 cies of shell, a small oval Lingula (Litigula umbonata,) which, by its 

 appearance, indicates the first traces of the marine element in the 

 shales. A few badly decayed leaves of ferns, and the Lepidostrobi, 

 (pi. 7, figs. 3, 5, 6,) are found on the same shales with the shells, evi- 

 dently showing that the vegetation had not entirely disappeared when 

 the marine water began to cover the marshes. This small Lingula, 

 always the only shell found at the same geological level in the shales, 

 not only in all the beds of the first coal in western Kentucky, but in 

 Ohio, at Nelsonville and other places; in Virginia, at great Kanawha 

 Salines; in Pennsylvania, at Rochester, Johnstown, &c; indicates 



*Tbis description is given only to facilitate the comprehension, but not at all as a scientific 

 and real one. The fruits of the coal, though their appearance may sometimes be the same, 

 do not bare, in reality, the slightest analogy with those of our time. 



