CARBONIFEROUS LYCOPODS AND SPHENOPHYLLS. 31 



Within the leaf-scar are three punctiform cicatricules, the central 

 being the vascular scar, the two lateral the parichnos. Fructifica- 

 tion in the form of cones, frequently if not always heterosperous, 

 terminal, or spirally or distichously arranged on the stem. 

 Sporangia single, attached to the upper surface of the basal 

 portion of the bract or sporophyll. Rhizomes, Stigmaria. 



III. Lepidodendron, Sternberg, 1820. 



IV. Lepidophloios, Sternberg, 1820. 

 V. Lepidostrobus, Brongniart, 1828. 



VI. Lepidophyllum, Brongniart, 1828. 

 VII. Stigmaria, Brongniart, 1822. 



(?) Stigmariopsis, Grand 'Eury, 1877. x 



C. BOTHRODENDRE^. 



Plants attaining to arborescent dimensions, ramifying by 

 repeated dichotomy. Leaf- cushions very feebly developed on 

 young twigs, absent on mature stem. Leaf-scars small, oval, 

 without prominent angles, cicatrices three, punctiform. Inter- 

 foliar portion of bark ornamented with fine longitudinal flexuous 

 strise or delicate shagreen. Leaves small, linear deltoid or 

 broadly lanceolate. Fructification in the form of cones of the 

 Lepidostrobus type, terminal or arranged distichously on the 

 stem. 



VIII. Bothrodendron, Lindley and Hutton, 1833. 



D. SlGILLARIE.E. 



Plants attaining to arborescent dimensions. Stem simple, 

 cactus-like, or very rarely dichotomously branched, smooth or 

 longitudinally ribbed. Interfoliar spaces of bark variously 

 ornamented. True leaf-cushions absent, but represented occa- 

 sionally by more or less prominent cortical projections. Leaf- 

 scars transversely rhomboidal, with generally prominent lateral 

 angles, frequently emarginate in the upper margin. Cicatricules 

 three, central (vascular), punctiform or transversely elongate or 

 sub-triangular, the lateral (parichnos) vertical, straight, or lunate. 

 Leaves single-nerved, linear-lanceolate, or long, narrow, and 

 grass like. Fructification strobiliform, stalked, forming irregular 

 verticils on the trunks or sessile, and placed in two opposite 



1 See p. 108. 



