234 
CLATHRARTA LYELLII. 
sandstone, attenuated at their base, the surfaces of 
which are marked with longitudinal interrupted 
ridges, and, in some instances, are deeply im- 
bricated ; they are generally of a dark brown colour. 
A specimen surrounded by the cortical covering, 
is represented Plate I. fig. 2., and a branched ex- 
ample of the interior, in Plate I. fig. 1. A cellular 
interstitial substance seems to have existed be- 
tween the internal part and the bark, and which 
is frequently found attached to the former, ap- 
pearing like a fibrous carbonized integument, 
an eighth of an inch thick. Cicatrices are oc- 
casionally seen on the stems (^7, «, fig. 1.), the 
nature of which has not been determined ; they 
have been supposed to indicate the setting off of 
branches, but in the ramose specimens, the ap- 
pearance is by no means similar ; they are more 
like what is observable in the Draccsna draco. 
“ This tree possesses a thin outer bark, marked by 
the cicatrices of the leaves ; and within that, an 
internal, somewhat reticulated surface, in which 
there is a singular plexus of the vessels, formed 
where the dragon’s blood was secreted, to which the 
cicatrix in the fossil vegetable bears a striking re- 
semblance.”* The casts of the internal axis of the 
fossil represent the true stem, and are composed of 
solid sandstone throughout, and show no traces of 
internal organisation, Plate I. fig. 1. ; the original, 
therefore, probably possessed a structure too deli- 
cate to be preserved by mineralisation. The recent 
plants which present the greatest analogy to these 
* Geolog. Trans, vol. i. p. 423. New Series. 
