408 SPHENOPHYLLUM. [CH. 



of the lamina. Several drawings have been given by Sterzel' 

 in a memoir on Permian plants, showing the variation in leaf- 

 form in Sphenophyllum emarginatum, but as Kidston^ and 

 Zeiller'' have pointed out Sterzel's specimens probably belong 

 to S. cimeifolium (Sternb.). 



Branches are given off singly from the nodes, and the cones 

 are borne at the tips of branches or branchlets. The cone of 

 S. emarginatum agrees very closely with that of S. cuneifoUum, 

 and is of the same type as that shown in fig. 108. The small 

 branch of S. emarginatum represented in fig. 109 does not show 

 clearly the detailed characters of the species, as the leaf-margins 

 are not well preserved. 



In one of the largest specimens of this species which I have 

 seen, in the Leipzig Museum, the main stem has internodes of 

 about 3'9 cm. in length, from which a lateral branch with much 

 shorter internodes is given off from a node. 



It is important to notice the close resemblance, as pointed 

 out by Zeiller, between some of the narrower-leaved forms of 

 S. emarginatuTn and S. cuneifoUum (Sternb.)*; but in the latter 

 species the margins of the leaves have sharp, and not blunt 

 teeth. 



The cone described and figured by Weiss* as Bowmanites 

 germanicus, since investigated by Solms-Laubach^, must be 

 referred to this species. Geinitz' figured a cone in 1855 as 

 that of 8. emarginatum, but his determination of the species 

 is a little doubtful. Good figures of the true cone of S. emar- 

 ginatum have been given by Zeiller* in his Flore de 

 Valenciennes, as well as in his important memoir on the 

 fructification of Sphenophylhim. 



2. Sphenophyllum trichomatosum Stur. Fig. 110, B. 



The finely-divided leaves of the single whorl shown in fig. 

 110, 5 (from the Middle Coal-Measures of Barnsley, Yorkshire), 



1 Sterzel (86), pp. 26, 27, etc. 2 Kidston (93), p. 333. 



3 Zeiller (88), p. 414. 



* Ibid. p. 411. •'' Weiss (84), p. 201, PI. xxi. fig. 12. 



6 Solms-Laubach (95"), p. 232. ' Geinitz (55), PI. xx. fig. 7. 



8 Zeiller (88), PI. lxiv. figs. 3—5, and (93), p. 24, PI. n. fig. 4. 



