218 



DR, AGNES AEBEE ON THE 



somewhat greater tlian would appear from these measurements. It is clear that, even 

 allowing for the full width not being seen in the sections available, the fructification 

 irtas unusually slender in proportion to its length. The pedicel, which was not less than 

 4 mm. long, was about 1 mm. in width near the axis, and slightly broader fui'ther out. 

 The lamina appears to have attained a length of 12 mm. or more, with, in addition, 

 a downward keel 2 mm. in length. None of the preparations are truly radial and the 

 apices of the sporophylls are, as a rule, either not preserved or missed in the sections, 

 with the result that a superficial examination would lead one to suppose that the lamina 

 was only about 5 mm. in length. The width of the sporopliyll at the level of insertion 

 of the ligule was about 6 mm. It will be recognised from this description that the 

 sporophyll, if found as a detached object in " impression material," would closely 

 resemble one of the spade-like examples of Lepidophyllum yx\i\ their narrow pedicels, 

 such as L. hrevifolium, Lesq., which has recently been recorded from the British 



Coal Measures*. 



(3) The Detailed Structure of the Cone Axis. 



Our knowledge of the anatomy of the cone axis is derived from a single transverse 



section. The axis was traversed by a vascular cylinder enclosing a pith (PL 23. figs. 11 



& 12). The cylinder is small, its diameter being about 0*3 mm. Between the proto- 



xylems and pith there are, on any radius, 3 to 4 large xylem elements. A marked 



characteristic of the axis is that the outer zone of the inner cortex {i.c) is formed of 



darker and more resistant tissue than the corresponding zone in the type specimens 



of Lepidostrohus oldhcmmis. The middle cortex is absent, and the firm outer cortex 

 is of the usual type. 



(4) The Sporophyll Traces in the Axis. 



The preservation is not sufiiciently good to allow the number of sporophyll traces, 

 cut across in a transverse section of the axis, to be determined with certainty, but it is 

 clear tJiat they were relatively few, probably not more than 20. 



Sporophyll traces, just on the point of leaving the axis, are shown in tangential 



section in PL 25. fig. 31. Each is accompanied by a large parichnos space. The trace 

 consists of a mass of xylem, in which no protoxylem can be recognised with certainty, 

 and a ventral crescent of .''phloem," separated from the xylem by a zone of parenchyma 

 (PL 25. fig. 34). The " phloem " evidently consisted of delicate thin-walled cells, for it 

 has suffered almost complete destruction. There are no transfusion elements in this 



region. 



r 



(5) The Detailed Structure of the Sjyorojihyll. 



Near the axis of the cone the pedicel is triangular in section, without an elongated 

 dorsal keel (PL 25. figs. 31 & 32). In this region it is composed, externally, of several 

 layers of dark, thick- walled cells, followed internally by a thin -walled zone, surroundmg 

 the parichnos space {par.). The vascular bundle is embedded in this thin-walled tissue 



* Arber, E. A. N. ('12), p. 252. 



