The Carboniferous Arborescent Lepidodendra. 31 



On the light thrown upon the question of the Growth 

 and Development of the Carboniferous Arborescent 

 Lepidodendra by a study of the details of their 

 Organisation. By W. C. Williamson, LL.D. and 

 F.R.S., Emeritus Professor of Botany in the Owens 

 College, Manchester. 



[Received October 25th, iSg^..'] 



Prior to the year 1832, when Witham published his 

 account of his newly discovered specimen of Lepidodendron 

 Harcourtii, nothing was known respecting the internal 

 organisation of the magnificent Lycopodiaceous Plants 

 found so abundantly in the strata of Carboniferous age. 

 The discovery of that specimen marked an epoch in the 

 history of Paleobotany. Sections of this important frag- 

 ment came into the possession of Adolphe Brongniart, then 

 our supreme authority in Palaeo-botanical subjects, and that 

 distinguished man described them with the greatest care in 

 the last published part of his "Histoire des Vegetaux 

 Fossiles." So far his work was admirably done, but 

 unfortunately he was led by it to adopt an erroneous 

 hypothesis, to which he clung to the end of his life. The 

 influence of his distinguished name caused this hypothesis 

 to be adopted by most of the then living Palseobotanists, 

 and it has been handed down to an entire generation of 

 their successors. In 1845, Corda obtained a second and 

 somewhat similar specimen ; but our real progress in 

 connection with these studies dates from about 1855, when 

 Mr. Binney discovered, in some of the lowest of the Lanca- 

 shire coal-seams, a vast number of Calcareous nodules, con- 

 taining remains of Carboniferous plants, in most of which the 

 C 



