390 Geological Society. 
and main roots, and the apparent lifting up of the latter out of the 
soil, in old trees, by the greater annual increase of the upper part or 
that nearest to light and heat. These phenomena in vegetation were 
illustrated by a diagram, which exhibited the form of the base of the 
stem and the root of a sapling, and of a full-grown tree. The author, 
in applying these characters to the fossils of the Manchester and 
Bolton railway, alludes to the irregular, longitudinal and disconti- 
nuous or anastomosing furrows on their surface, to the swelling out at 
the base of their stems, and to the divergence as well as the angle 
of dip or downward direction of their roots. These characters, he 
says, are not observable in soft monocotyledonous trees, their stems 
never expanding laterally, and being as thick when only a few years 
old and a foot high, as when they attain the height of 60 or 100 feet. 
Their roots also, instead of being massive and forking, generally pre- 
sent a dense assemblage of straight succulent fibres, like those of an 
onion or hyacinth. Analogy, therefore, as far as outward shape and 
habit are concerned, he adds, is strongly in favour of the fossils 
having been solid timber trees. 
Mr. Bowman then combats the view, generally entertained, that 
fossil stems with perpendicular furrows, as in the Sigillaria, were 
succulent or hollow plants*. He states, that good specimens of de- 
corticated Sigillaric exhibit fine straight, and curled or gnarled strie,, 
similar to those on the alburnum of many modern forest trees ; and 
that this character, in conjunction with others, renders it almost cer- 
tain, that the fossils had a separate back,—a feature which is consi- 
dered in vegetable physiology to be a proof of a woody structure. 
He also alludes to the existence in many of the decorticated parts of 
their fossil trees of little prominences like those in barked timber; 
likewise to the scars left by the disarticulation of leaves; and he ac- 
counts for the general absence of the latter on large and old trunks, by 
their having been obliterated, in consequence of irregular expansion 
from the deposition of new layers of wood: he notices moreover the 
absence in small Sigillariz of the irregular furrows observed on large 
specimens, and due in his opinion to the unequal expansion by the 
addition of new layers of wood. In support of these proofs of the 
original solid nature of the trees, Mr. Bowman exhibited polished 
slices mounted upon glass of portions of a similar fossil tree dis- 
covered in sinking a shaft 300 or 400 yards N.W. of those found on 
the line of the railway. The slices were made from a portion which ex- 
hibited within the carbonized bark, a patch browner, heavier, and more 
compact than the rest. In these slices, made under Mr. R. Brown's 
direction, that gentleman discovered in the transverse section, the 
uniformity of vascularity which is evidence of coniferous structure ; 
and in the longitudinal section parallel to the medullary rays, the ex- 
* Specimens of recent dicotyledonous wood from New Zealand, lent to 
the author by Mr. R. Brown, were exhibited on the table of the Meeting 
Room. ‘They displayed both upon the bark and the naked wood, longitu- 
dinal ribs and intermediate furrows as regular as those on Sigillariz ; and 
therefore prove that these characters are not incompatible with a dicotyle- 
donous structure. 
