ENDOGENITES EROSA. 
237 
wliich is removed by washing. The external sur- 
face is scored with small meandering grooves, and 
dee]) longitudinal furrows ; a transverse section 
exhibits numerous pores, formed by the division of 
vessels, proving the monocotyledonous structure of 
the original (vide PI. I. fig. 5.) ; and a magnified 
])ortion of the outer surface is shown PI. I. fig. 4. 
The constituent substance of these fossils is a 
dark grey sandstone ; tlie cavities of the vessels 
are generally lined with crystallised quartz ; and 
the fissures are frequently filled with white cal- 
careous spar. We are not acquainted with any 
recent or fossil vegetables that are identical with 
this endogenite. M. Adolphe Brongniart informs 
us, that it bears some resemblance to the base, or 
the short and almost subterranean stems, of some 
recent species of ferns, that are not arborescent. 
Mr. Stokes observes, that a mass of monocotyle- 
donous wood, from Upper Egypt, figured in the 
great work on that country, published by authority 
of the late Emperor Napoleon, has considerable re- 
semblance to this, fossil : and among some interest- 
ing specimens of the trunks of fossil palms, 
from Antigua, presented to us by the Honourable 
Mrs. Thomas, of Ratton, near Eastbourn, there 
are examples which expose a structure in many 
respects analogous. M. Brongniart is inclined to 
refer it to the arborescent ferns, rather than to the 
Palms.* 
• Prodrome d’une Histoire des Vegetaux Fossiles, par M. Adolphe 
Brongniart, Paris, 1828. 8vo. 
