May 1900.] BOTANICAL SOCIETY OF EDINBURGH 295 



in the size of the other cones on the axis ; but there were 

 exceptions to this last, in that the apical cone might be 

 longer than the average. Further, sterilisation was usually 

 associated with reduction in size of the cone. Taking the 

 average length of a normal fertile cone at the figure stated, 

 we find the length ratio of sterilised to normal cone as 3 

 to 8. 



Sporophyll variations were studied in dissections of 

 branched and sterilised cones. The normal sporophyll 

 may be described as ovate in outline, contracted basally, 

 and continued at the apex into a long hair-like prolonga- 

 tion. Its margins are irregularly serrate. Its length is 

 about 5, and its breadth about 2 mm. The ordinary 

 foliage leaf, again, is narrow elongate- lanceolate, simple, 

 sessile, with its apex also prolonged into an awn-like 

 structure. Its margin is not appreciably serrate. Its 

 length is about 7 to 8, and its breadth | mm. 



No variation of the nature of lobing or branching of the 

 sporophyll was met with, but forms intermediate between 

 sporophyll and foliage leaf occurred. These were to be 

 seen occasionally in the middle of such a semi-sterilised 

 cone as that of Fig. 9 (Plate II.). These intermediate 

 sporophylls were about 1 mm. in breadth, and about 

 6^ mm. in length ; the outline was similar to that of the 

 foliage leaf, but the apical prolongation was shorter, and 

 resembled that of the normal sporophyll, and further, 

 there was a slight indication of marginal serration. Such 

 intermediate leaves had sporangia, so that the metamor- 

 phosis of cone into foliage shoot would appear to be 

 first manifested in the change of the sporophyll. 



For the study of the branching serial sections, radial, 

 tangential, and transverse of young and old, branched, 

 and partially and completely sterilised cones were prepared. 

 I hoped to discover some variation in histological structure, 

 but as yet I have nothing to record on this head. 



These preparations were also carefully • searched for 

 variations in the sporangia, for a possible branching — 

 the occurrence of which would be both interesting and 

 important. On dissecting similar strobili, I found among 

 the normal sporangia of a reniform or horse-shoe shape 

 others whose shape varied. Some were bulkier than usual. 



