THE CYPEESS SUB-FAMILY. 315 



19. THUJA, Tournefort. WESTERN, OR AMERICAN 

 ARBOR VITJ3. 



Flowers monoecious and terminal, on different branches ; 

 sterile aments, elliptical or ovoid ; fertile aments, ovoid 

 and solitary. Cones small, ovoid, with from 4 to 6 coria- 

 ceous scales, the latter spreading, adherent at the base, 

 and covering 2 seeds, winged all round the margins. Co- 

 tyledons, 2. Leaves small, scale-like, or awl-shaped, oppo- 

 site / appressed, and imbricated in 4 rows on the flat 

 branchlets. 



The American Arbor Yitses in ornamental plantations 

 bear a conspicuous part ; for not only do they form desira- 

 ble specimen trees, but are useful in forming screens and 

 hedges. They bear the knife or shears with perfect impu- 

 nity, the plants thickening up to a degree of density rare- 

 ly surpassed by any other evergreen. And then again, 

 the comparative cheapness of the type of the genus and 

 the readiness with which it will grow and flourish in al- 

 most any soil are additional incentives to its increased 

 cultivation. 



The timber is reputed to be very durable. Name prob- 

 ably derived from thy on, " sacrifice ; " or from the ancient 

 Greek name of some resin-bearing tree. The origin of the 

 common name Arbor Yita3 is involved in obscurity ; some 

 writers say it was introduced into England under that 

 title, but the reason for it is unknown. 



1, T. gigantca, Nuttall. GIGANTIC AEBOR YITJE. 

 Leaves acute, incurved, ovate, quadrately and closely im- 

 bricated, entirely destitute of the glandular tubercle, bright 

 green or occasionally glaucous-green in color, and exceed- 

 ingly beautiful, resembling the fronds of a fern. Branches 

 and branchlets, erect, somewhat flattened, regular in ar- 

 rangement, long, and slender. Cones abruptly recurved, 

 more clustered and drooping than in T. occidentalis^ oth- 

 erwise very similar. Seeds elliptic and furnished with a 

 wide winged margin. 



