160 LYCOPODIALES [CH. 



points out, some of the outermost cells of the lacunar cortex 

 (m) are clearly in a state of meristematic activity. 



The preservation of the middle cortex and the small quan- 

 tity of secondary xylem are characters which this Stigmaria 

 shares with Lepidodendron fuUginosum, and although decisive 

 evidence is still to seek, we may express the opinion that 

 Weiss's surmise of a connexion between Stigmaria radiculosa 

 and Lepidodendron fuUginosum is probably correct. 



5. Lepidodend,ron Harcourtii. Fig. 179, A — D. 



In 1831 Mr Witham^ published an anatomical description of 

 a fragment of a Lepidodendron which he named Lepidodendron 

 Harcourtii after Mr C. G. V. Vernon Harcourt from whom the 

 specimen was originally obtained. The fossil was found in rocks 

 belonging to the Calciferous series in Northumberland. Witham 

 reproduced the account of this species in his classic work 

 on Fossil Vegetables^, and Lindley and Hutton', who examined 

 Mr Harcourt's material, published a description of it in their 

 Fossil Flora in which they expressed the view that Lepidoden- 

 dron is intermediate between Conifers and Lycopods. Adolphe 

 Brongniarf included in his memoir on Sigillaria elegans an 

 account of Witham's species based on material presented to the 

 Paris Museum by Mr Hutton and Robert Brown. Dr Kidston^ 

 has shown that the actual transverse section figured by Witham 

 is now in the York Museum; a piece of stem in the same 

 Museum, which is not the specimen from which Witham's 

 section was cut, supplied the transverse section figured by 

 Brongniart. The figures given by Lindley and Hutton do not 

 appear to have been made from the York specimens. In 1887 

 Williamson" published a note in which he pointed out that some 

 of the specimens described by him as L. Harcourtii should be 

 transferred to a distinct species, which he named L. fuUginosum. 

 Subsequently in 1893 he gave a fuller account of Witham's 

 species; it has, however, been shown by Dr Kidston and by 



1 Witham (31) A. 2 Witham (33) A. Pis. xii. xiii. 



3 Lindley and Hutton (35) A. Pis. 98, 99. •> Brongniart (39) A. 

 5 Kidston (03) p. 822. « Williamson (87). 



