85 
The Holly Bush seam and those above have over them fossils, 
common to all though not equally numerous; the top vein is 
especially characterised by well-preserved specimens of 
Calamites. Over the Top vein occurs the true type of Sigillaria 
pachyderma and some of the strata between the Top and Holly 
Bush seams are full of the foliage of Lepidodendra. 
The following is a complete list of the Flora of the Upper 
Series :—Lepidodendron Sternbergui, longifolium, aculeatum, elegans, 
decorticata, rimosum ; Sigillaria pachyderma, scutellata, elongata, 
subrotunda, intermedia; Stigmaria ; Calamites decoratus, radiatus, 
of the latter we figure a specimen with roots attached (Fig. II), 
the rhizoma appears to have continued on and to have broken 
off ; Ulodendron commutatum ; Alethopteris lonchitica, wrophylla, 
Bucklandi ; Pecopteris arborescens, nodosa ; Neuropteris cordata, 
Soretii, flecuosa ; Rhacophyllum lactuca ; Carpolithes sulcata, and 
Cordaites, with reeds and grasses. 
The unfortunate feature by which the hard vein may be 
especially known is the occurrence of small coalstones, some- 
times in such numbers as to make the coal almost worthless. 
After an examination of these stones and some which occur 
in the great vein of the Lower Series, I have been unable to 
arrive at their origin. They consist of an inorganic nucleus (in 
which there is a considerable proportion of iron), surrounded 
by a covering of carbonaceous substance. 
On this are the markings of Stigmaria, and of the other tree 
plants of the period ; the one figured is that with the marks of 
Stigmaria (Fig. ITT). 
Were these bodies found over or under the coal, they 
would be placed in cabinets as fossils, but because they occur 
in the coal they are simply stones. They are, however, as 
much fossils as those found under or below. 
The shape suggests their origin, it is the same as those of the 
other fossils; they were probably the hollow branches and 
roots of trees filled with debris, somewhat in this way. 
It is tolerably certain that at least some of our coal-fields 
have been formed near the deltas of great rivers; into these rivers 
we see no reason why trees should not have been carried by 
