PALiEOZOIO CONE-GENUS LEPIDOSTROBUS. 221 



(2) General Form and. Dimensions of the Cone and Sporophylls. , 



The specimen consists of the apical portion of a cone of which the base has been 

 destroyed, so that it is impossible to determine the dimensions of the fructification as 

 a whole. The length of the existing fragment is nearly 2*5 cms. The sporophylls to 

 one side are slightly damaged ; if they were complete the greatest diameter would be 



The axis is 3 to 4 mm. in width. The apices, both of the cone as a whole 

 axis, are noticeably obtuse and rounded. The laminae of the sporophylls 



eras 



and of the 



and protect the apex (PL 23. figs. 13 & 14) 



The sporophylls spring from the 



very slightly less than a right angle 



(PL 23. fig. 13 and PL 26. fig. 43). It should be recalled, however, that the angular 

 relation of sporophyll to axis may vary in different regions of the same cone. We 

 are here dealing only with the apical part of the strobilus, so it is unsafe to lay much 

 stress on this character. The laminae of the sporophylls are relatively short. The 

 pedicel is nearly 6 mm. long and apparently from 1-2 mm. wide, whereas the upturned 

 part of the lamina seems to be only 3-4 mm. long, and the downward heel about 1 mm. 

 The width of the lamina appears to have been 3-4 mm., but the absence of transverse 

 sections makes it impossible to check the accuracy of this statement. The uncertainty 

 connected with measurements of the sporophyll in petrified material has been referred 

 to on p. 212, but it is at least clear that in this case as in Zepidostrohus gracilis, it was 

 of the " spade" type, without a broadly winged pedicel. In Z. oldhamius f. minor the 

 pedicel appears to be longer and the lamina smaller than in L. gracilis. 



(3) The Cone Axis. 



The detailed structure of the cone axis cannot be ascertained, owing to the absence 

 of transverse sections and to the fact that in the longitudinal sections the vascular 

 cylinder is not in any case preserved. The outer cortex consists of the usual elongated 

 cells with firm walls. 



(4) The Sporophyll Traces in the Axis. 



On examining the section which is photographed in Pi. 23. fig. 13, the outgoing 

 sporophyll traces are found to be cut almost longitudinally, although the outer cortex is 

 traversed tamgentially . This indicates that the course of the sporophyll traces, at least 

 in the outer region of the axis, was markedly steep. 



(5) The Detailed Structure of the Sporophylls. 



The sporophyll pedicel is triangular in section, and the dorsal keel is scarcely 

 developed (PL 23. fig. 14 and PL 26. figs. 46 & 47). There are slightly raised sclerised 

 cushions on the ventral surface to right and left of the median line. The outer la) 

 of the pedicel consist of thick-walled sclerised tissue, and the inner 

 not preserved. The result is that the pnrichnos appears to be larger than it was durin 



thin-walled 



SECOND SERIES.— BOTANY. VOL. VIII. 



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