58 CALLITRIS. 



but one under each. Seeds winged on each side, slightly com- 

 pressed, and somewhat three-edged. 



Seed-leaves, from three to six, but mostly in fours. 



Leaves, very small, scale-formed, in alternate opposite pairs, 

 close together at the base of the joints. 



Name derived from " Kallos," beauty, from the elegant and 

 regular appearance of the jointed branchlets. 



Callitris quadrivalvis, Ventenat, the jointed Arbor- Vitse. 

 Syn. Thuja articulata, Wahlenberg. 

 Frenella Fontanesii, Mwbel. 



Leaves very small, scale-formed, in alternate opposite pairs, 

 close together at the base of the distant joints, and facing four 

 successive ways, those on the margins clasping both sides, those 

 on the upper and lower sides flat, with a terminal point and 

 small transparent gland near their extremity ; those on the 

 adult branches are very much smaller and decurrent. Branches 

 spread out horizontal, with numerous lateral ones, regularly 

 dividing again into flattened, slender jointed, shining, smooth, 

 pale green branchlets. Branchlets numerous, regularly branch- 

 ing, quite flat, glabrous, sometimes glaucescent, distinctly jointed 

 and straight. Cones globular, or somewhat quadrangular, and 

 consisting of four scales or valves, in opposite pairs, regu- 

 larly truncate on the summit, slightly concave and obtuse ; the 

 two opposite ones much longer and seldom convex, but termi- 

 nating in a point at the extremity, and containing one or two 

 double- winged seeds under each. 



A large tree, diminishing into a small bush, according to 

 elevation and soil; found on the mountains of Barbary in 

 rocky situations, and on Mount Atlas, in Northern Africa. 



Its Barbary name is " Alerce." 



It is not hardy, except in the milder parts of England. 



