116 MR. W. C. WORSDELL ON THE 
extrafascicular ring into a number of concentric strands. This latter condition I hold, 
as elsewhere stated, to represent the most primitive type, from which the collateral ring 
has been derived. Therefore Gregg’s fig. 4 shows us the most primitive type of 
structure, his figs. 1 and 3 an advance thereon in the direction of the ordinary collateral 
rings of the Cycadean stem. 
Hitherto the phenomenal structure discovered by Gregg has remained inexplicable ; 
in the light of further researches it is now seen to possess important bearings on the 
phylogenetie relationships of the plant concerned; and I may remark that the mere 
observation of structures is comparatively useless unless at the same time their 
meaning and significance are ascertained. I hope I have succeeded in so doing. 
ENCEPHALARTOS LANUGINOSUS, Lehm. 
Male Cone. 
The structure of the peduncle is of great interest, exhibiting, in rather more primitive 
form, the same structure as is found in the vegetative axis. This is what one would 
naturally, à priori, expect, seeing that the cone is the most primitive axial organ of 
the plant. 
Besides the central cylinder are numerous extrafascicular strands of varying sizes and’ 
shapes, some of which are very much elongated tangentially, consisting of many segments 
and perfectly straight, while others are more or less curved in contour (Pl. 16. fig. 8). 
Some of the strands are built up of two or three bundles or segments, arranged 
concentrically, with their xylems turned towards each other so as to form a loosely- 
compacted concentric strand (Pl. 15. figs. 7 & 9). Here and there may be seen two strands, 
of which one is normally and the other, opposed thereto and nearer the cylinder, inversely 
orientated. In one place a tiny concentric strand, constituted of three distinct parts, 
lies between the central cylinder and a large collateral normally-orientated strand. At 
many points the strands of the central cylinder bend outward, just as do those in the 
stem of Medullosa* when connecting with the strands of the first extrafascicular ` 
ring, or giving off leaf-traces, and as is also seen in the lower part of the peduncle of 
Stangeria. 
The extrafascicular strands are larger and more frequent above the base of the organ, 
in the lower part fewer and smaller. A curious deep invagination has been formed by 
the cylinder iu one place (Pl. 15. fig. 9). 
A very few minute foliar traces occur in the outer part of the cortex, either singly 
or in pairs. 
All the extrafascicular strands of the peduncle I regard as homologous with the 
concentrically-built strands occurring outside the central cylinder in the region of 
the primary node of the vegetative axis of Cycas, Encephalartos, and Macrozamia, as 
also with the extrafascicular collaterally-built zones of these three latter genera and 
of Bowenia. 
* Weber & Sterzel, Beiträge zur Kenntniss der Medullosesm, pl. 4. fig. 2, pl. 5. fig. 2. Scott: “The Anatomical 
Structure presented by the Peduncles of Cyeadacez;" Ann. Bot. vol. xi. 1897, pp. 398-419, figs. 1 & 2. 
