6 GNETACEAE. 
EPHEDRA. Ca/fatillo. 
(Family Gnetaceae). 
Scragely shrubs. Twigs green, 
finely striate and usually granular, 
elongated, straight and slender: 
pith round, red-brown, resinous, 
continuous except for firm pale 
diaphragms at the nodes. Buds 
solitary, sessile, ovoid, small, with 
about 3 pairs or whorls of scales 
or the flower-buds collaterally mul- 
tiple and developing into large 
thin-scaled “cones” in fruit. Leaf- 
scars and stipule-scars tacking. 
Leaves reduced to scarious scales, 
connately opposite or whorled. 
The heterogeneous family Gneta- 
ceae, represented here by Ephedra, 
though now considered to belong 
to the group of Gymnosperms was 
long held to be angiospermous, and 
it combines the characters of these 
superior groups in so puzzling a 
way that its present taxonomic location is more tenable on 
grounds of embryogenesis than for other reasons. Like the 
Angiosperms, its secondary wood produces true vessels, the 
other Gymnosperms containing tracheids only. 
1. Leaf-scales opposite in pairs, ovate, brown, soft. 2. 
Leaf-scales in whorls of three. 3. 
2. Seales very short (1-2 mm.). E. viridis. 
Seales moderate (4-5 mm.), sheathing. EH. antisyphilitica. 
3. Seales short (3 mm.), soft. E. Torreyana. 
Seales elongated (10 mm.), subpungent. E. trifurca. 
