957 
the Inflorescences and Flowers of Ephedra. 
The varied distribution of the lignified tissue in the different species 
of this genus is paralleled in Welwitschia , where in the male inflore- 
scence the entire pith is lignified, while in the female inflorescence this 
happens only in the extreme base ; elsewhere lignification is confined to 
strands of tissue on the periphery of the pith accompanying the vascular 
bundles. 1 
(ii) Vascular Anatomy of Naked Axis. In E. distachya the peduncle 
is traversed by eight collateral bundles, oc- 
curring in a regular ring and remaining un- 
branched except where, in the male inflore- 
scence, branching of the axis occurs. At this 
level and at the branchings of the axis of the 
female inflorescence in E. altissima , the be- 
haviour of the bundle system is similar to that 
described later in connexion with the vegeta- 
tive buds in the axils of the ordinary vegetative 
leaves. In the upper branches of the female 
peduncle of E. altissima the structure is some- 
what different ; there are here four small 
bundles and two large ones, which latter are 
seen by their behaviour in the strobilus each to 
represent two of the bundles in the lower parts of the peduncle. 
(c) Anatomy of the Female Strobilus. 
The axis of the strobilus itself is similar in general structure, distribu- 
tion of fibres, &c., to the naked axis bearing the strobilus. In describing 
the course of the vascular bundles in the axis of the female strobilus it will 
be necessary to treat the two species specially examined separately. 
(i) E. distachya. The eight bundles which enter the base of the stro- 
bilus become arranged in two groups separated from one another by gaps 
in the ring (Text-fig. ll. i). Then the bundles on either side of each gap 
(Text-fig. II. 2 and 3, B) pass out to the first pair of bracts. 
Four bundles are left in the axis ; these now divide to form again the 
original number (Text-fig. II. 4). Next the eight bundles are rearranged 
into two groups at right angles to the previous arrangement, and two pairs 
of bundles pass out to the second pair of bracts (Text-fig. II. 5 and 6, b 2 ). 
Four bundles are again left in the axis and once more divide to form 
eight, arranged in two groups corresponding in position to those below the 
first pair of bracts. Before, however, the lateral members of each group 
pass out to supply the third pair of bracts, a small bundle originates from 
each of them and fuses with the opposite one in the gap between the 
Text-fig. i. Transverse sec- 
tion of peduncle of E. altissima 
near the base of a strobilus, showing 
six bundles, lignified pith (p), and 
fibres scattered in the cortex (f). 
1 Sykes, 1910, pp. 191 and 201-2. 
