230 



THE CULTIVATED EVERGREENS 



scale-like bracts at the base of the cone: leaves ternate, scale-like, sometimes 

 needle-shaped: cone ripening the first year, with 6 acute valvate scales 

 surrounding a conical production of the central axis; each scale with 2 winged 

 seeds. The only species is A. pyramidalis, Miq. (Callitris Adinostrohus, F. 

 Muell.), a densely branched shrub with a 

 cone about f inch across, from West Aus- 

 tralia. — Cultivated in Europe about 1845. 



9. TETRACLINIS, Mast. ARAR-TREE 



Evergreen tree; branchlets articulate, 

 flattened: leaves scale-like, minute, in 

 whorls of 4 : cones tetragonal, consisting of 

 4 valvate scales of nearly equal size, the 

 outer pair concave on back, the inner pair 

 depressed on back and usually sterile, all 

 with a small mucro below the apex; fertile 

 scales with 2 or 3 broad-winged seeds. 

 (Name derived from Greek, tetra, four, and 

 klinis or Icline, bed; referring to the num- 

 ber and shape of the cone-scales). — One 

 species in northern Africa. 



T. articulata, Mast. {Thuya articulata, 

 Valil. Callitris quadrivalvis. Vent.). Arar- 

 Tree (Sandarach-gum-Tree). Fig. 51. 

 Small tree to 20 feet tall, with slender 

 spreading branches: the free apex of the leaves triangular, glandular: 

 cones about 3^ inch across; scales oval. Mountains of northwestern Africa. 

 — Introduced in 1815 to Great Britain and occasionally cultivated in Euro- 

 pean gardens and in California. It is probably not hardy north of the Southern 

 States and California. The arar-tree has some resemblance to Thuja orien- 

 talis, but the habit is looser and the branchlets slenderer. It furnishes gum 

 sandarach, a varnish resin. 



10. WIDDRINGTONIA, Endl. 



Evergreen trees; branchlets terete: leaves opposite, scale-like or linear, on 

 leading shoots alternate and linear: flowers dioecious; staminate flowers 

 solitary and terminal: cones ripening the second year; scales 4, valvate, 

 equal, usually tuberculate and angular on back; each scale with 1 to many 

 winged seeds. (Named for Samuel Edward Widdrington [formerly Cook]; 

 wrote on Conifers; died in 1856). — Five species in tropical and South Africa 

 and Madagascar. 



Tetraclinis articulata. 



