955 
the Inflorescences and Flowers of Ephedra. 
Occasionally, however, a form with two ovules is met with in which the 
arrangement of the ovules is the same as that found in the other species ; 
but in this case no sign of the stem apex could be detected, the two outer 
integuments being fused together at the base. 
The ovule has two coverings similar in position and character to those 
immediately surrounding the ovules in the other Gnetales, and here regarded 
as the outer and inner integuments. 
The male strobilus is similar to the young female, but above the single 
basal pair of sterile bracts there are several pairs of fertile bracts, in the 
axil of each of which is a male ‘ flower The male flower consists of two 
perianth segments and a stalk, frequently more or less bifid, bearing two 
groups of bilocular synangia (Figs. 4-6, PI. LXXXV). The number of the 
synangia varies from eight in E. distachya and nebrodensis to two in 
E. altissima. 
In E. fragilis , var. campylopoda , the strobilus is bisexual, with male 
flowers in the axils of the lower pairs of fertile bracts and ovules in the 
axils of the uppermost pair. The latter, however, never reach full develop- 
ment. 
The strobili of Ephedra are obviously far more closely comparable 
with those of Welwitschia 1 than with those of GnetumI The branched 
male inflorescence with its compact strobili, and both male and female 
strobili with their basal sterile bracts and their upper fertile bracts with 
axillary sporangiophores, are strikingly similar in both genera, but in 
Ephedra the strobilus has a much more limited growth than in Wel- 
witschia. 
II. The Anatomy of the Inflorescences and Flowers. 
(a) The Bracts. 
The bracts of both male and female strobili are similar in character, 3 
though those of the female are tougher in the early stages than those of the 
male, and also undergo later various changes connected with the ripening of 
the fruit, becoming, in the different species, succulent or chaffy, &c. The 
members of each pair are fused together in the female strobilus, but only 
slightly connate at the base in the male. 
Each bract receives two vascular bundles, which run unbranched nearly 
to its apex. As in the vegetative leaves, the bundle is accompanied by 
a small number of reticulate transfusion tracheides, occurring laterally in two 
groups (Fig. 7, PL LXXXV). These increase in number and size towards the 
apex of the bract, where the bundles approach one another. Finally, the 
endings of the bundles are lost in one common group of transfusion tissue 
1 Pearson, 1906, 1909; Sykes, 1910. 2 Thoday (Sykes), 1911; Pearson, 1912. 
3 Stapf, 1889, pp. 25 ff. ; Bertrand, Fig. 12, PI. Ill, figure showing similar structure of 
vegetative leaf. 
3 R 2 
