140 



FOSSIL PLANTS. 



Fig. 2 (magnified 6 diameters) is a longitudinal section of the same specimen, 

 showing the space formerly occupied by the medulla, but now only containing a little 

 disarranged tissue {a), the smaller tubes next the medulla, barred on all their sides, 

 forming the inner radiating cylinder (c), traversed by one of the large vascular bundles 

 {(1), proceeding from the medulla towards the outside and the bell-shaped cavity 

 containing the vascular bundle [d), traversing the zone of lax parenchymatous tissue (e), is 

 well shown on the left-hand side of the figure. 



Fig. 3 (magnified 8 diameters) is a tangential section of the same specimen, showing 

 the large oval vascular bundle {d), and the numerous small medullary rays of single cells 

 in vertical series {d') traversing the woody cylinder. 



Fig. 4 (natural size) is a representation of the outside of the specimen, showing cica- 

 trices of rootlets. 



Specimen No. 42, fig. 5 (natural size), shows a beautiful pyritized specimen of 

 8tigmaria jicoides^ the common open-wedged form, from the Lower Coal-measures of 

 Lancashire (the exact locality not known), exhibiting the inner radiating cyhnder in a 

 perfect condition, with the inner ends of the wedge-shaped masses of the woody cylinder 

 pierced by elongated oval cavities, in which were the large vascular bundles communi- 

 cating with the central axis and proceeding to the rootlets. 



Fig. 7, specimen No. 43 (magnified 6 diameters), represents the inner portion of 

 another pyritized specimen from the " Stinking Two Row Seam" of coal at Golden Hill, 

 North Staffordshire, in which the parts of the wedge-shaped masses of the woody 

 cylinder next the medulla not only show the large oval orifices described in No. 42, but 

 also traces of the small medullary rays seen in the tangential sections of the inner parts. 

 This specimen is close-wedged, and is a portion of that described by me in the ' Quarterly 

 Journal of the Geological Society,' and contains the large tubes in the central axis which 

 some writers have taken to be the rootlets of other Stigmarim that have invaded the 

 medullary portion of the plant. 



The oval openings {d) seen on the ends of the wedge-shaped masses of the woody 

 cylinder are all arranged in quincuncial order, exactly the same as the rootlets are on the 

 outside of the root, and doubtless contained the vascular bundles which proceeded from 

 the medulla and communicated with the rootlets. 



1 This is part of a specimen which many years ago led me to search all the Lower Coal-measures of 

 Lancashire and Yorkshire for a long time, until I discovered the calcareous nodules in the " Brooksbottom " 

 and " Upper Foot Coals " near Burnley, Oldham, and Halifax, yielding specimens showing structure, 

 about twenty years since. 



