106 DESCRIPTIVE CATALOGUE 



V. 6453. A piece of a branch about 4 cm. in diameter and 

 13 era. long, embedded in a coarse iron-stained 

 matrix. The exposed end of the wood, which is broken 

 across transversely, shows several well-marked annual 

 rings of secondary wood round the central axis. At 

 the other end of the specimen the wood is extremely 

 friable, so that a fine brown powder can be readily 

 detached. This powder is principally composed of 

 short lengths of isolated tracheids. Under the micro- 

 scope these can be rendered transparent, and they 

 then show a single row of round bordered pits along 

 their walls. Locality unknown. 



Transferred from the Botanical Dept. 



1767. The specimen at first sight appears to be a pith-cast, in 

 some degree resembling the Bucklandia type of fossil. 

 The cast is of some size, measuring as much as 

 (X 18 cm. On either side of the cast there are some 

 imperfect remains of secondary wood, in a white 

 pulverising condition. Small portions of this wood 

 can be detached, and they break up into a fine while 

 powder which largely consists of short lengths of 

 isolated tracheids. Jn some of these, microscopic 

 examination reveals the presence of round bordered 

 pits lying in a single row, which is characteristic of 

 the higher Gymnosperms. It is therefore hardly likely 

 that the pith would have been as much as (j cm. in 

 diameter, and the cast probably represents not the 

 pith but the inner zones of wood, which must have 

 been decayed before the petrifaction took place. 

 Kentish Hag; Iguanodon Quarry, Maidstone. 



Presented by W. H. Bensted, Esq., 1839. 



6049. A small piece of black carbonised wood (5-5x4 cm.), 

 partly embedded in the coarse sandy matrix. The 

 wood is very friable, and the detached and suitably 

 treated tracheids show a single row of round bordered 

 pits on their walls. Locality unknown. 



Mantell Coll. 



