1894.] of fossil plants, with a list of type specimens. 193 



afford any adequate idea as to the nature of the complete frond ; 

 the form of the pinnules suggests rather an alethopteroid than 

 pecopteroid type of fern. 



Lepidodendron ? binerve Bunb. 



Quart. Journ. Geol. Soc. Vol, ill. 1847, p. 431, PI. xxiv. fig. 2. 



Cape Breton, Nova Scotia. Coal- Pleasures. 



This species is founded on the occurrence of two longitudinal 

 ribs in the small leaves of the terminal branch fragments figured 

 by Bunbury. In one of the specimens the ribs are apparently 

 not shown; in the other they are faintly indicated. It is doubtful 

 how far this character affords sufficient grounds for the institution 

 of a new species; possibly, as Kidston^ suggests, in the case of 

 Lepidophylliim binerve, figured by Lebour^, the supposed existence 

 of two veins rests on an accident of fossilization. It is conceivable, 

 however, that the "double" leaf-trace oi Lepidodendron Harcourtii 

 With, may be recognised in well preserved leaves as two distinct 

 vein-like ribs. 



Lepidodendron tumidum Bunb. 



Quart. Journ. Geol. Soc. Vol. ill. 1847, p. 432, PI. xxiv. fig. 1. 



Cape Breton, Nova Scotia. Coal-Measures. 



Bunbury speaks of this species as "one of those ambiguous 

 forms which would be referred by some to Lepidodendron, and 

 by others to Sigillaria." He compares it with L. ottonis Goepp. 

 and Sigillaria Brardii Brong. Schimper^ refers Bunbury's plant 

 to the genus Lepidophloios, and Macfarlane* apparently accepts 

 this opinion. Kidston^ considers, on the other hand, that 

 Sigillaria should be substituted for Lepidodendron as a more 

 fitting designation for this "ambiguous form": in this I thoroughly 

 agree with him. The leaf-scars are rather farther apart than in 

 many specimens of Sigillaria Brardii, but the great variation in 

 the appearance of this species has been well illustrated by Zeiller" 

 and Weiss'', and should serve as a warning not to attach any great 

 importance to the distance between individual leaf-scars on small 

 fragmentary specimens. 



Bunbury's figure gives one the impression of prominent and 

 more or less well-defined leaf-cushions, each terminated by a leaf- 



1 Trans. E. Soc. Edinburgh, Vol. xxxv. Pt. i. 1888, p. 323. 



2 lUust. fossil plants, 1877, PL lii. 



3 Loc. cit. Vol. II. p. 52. 



4 Trans. Bot. Soc. Edinburgh, Vol. xiv. p. 182. 



5 Annals Mag. Nat. Hist. Series 5, Vol. xv. 1885, p. 359. 

 « Bull. Soc. G^ol. France, S^r. 3, Vol. xvii. 1889, p. 603. 



'' Zeitsch. deutsch. geol. Ges. 1888, p. 565. (For an abstract of the two last 

 papers, see Seward, Geol. Mag. Dec. iii. Vol. vii. 1890, p. 213.) 



VOL. VIII. PT. III. 14 



