270 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Seeds in twos at tlie base of each scale, and furnished with a trans- 

 parent wing, emarginate at the end. 

 Cotyledons two. 



Leaves in opposite pairs, very small, scale-like, imbricated, com- 

 pressed, and in four rows. 



The name Thuya is derived from " Thyon " (sacrifice), in conse- 

 quence of the twigs and resin being formerly used in the East instead 

 of incense in sacrifices. The common English name, Arborvitfe (tree 

 of life), is derived from its Chinese and Japanese ones. In Japan it is 

 called "Hiba" (tree of life), and in China " Hak " (everlasting life), 

 on account of the plants being evergreen, and of a lively or bright 

 green at all seasons of the year. But as the genus Thuya is now 

 defined, only one of the Chinese or Japanese kinds belongs to it, all the 

 others being transferred to that of Biota. 



Of the section Eutliuya (Benth. and Hook.) one species is from 

 eastern North America, and one from the western parts of that con- 

 tinent. Of the section Macrothuya (Benth. and Hook.) only one 

 species is from North America from western parts, and another 

 species strictly belongs to Japan. 



T. gigantea, Nutt. PI. of Eock. Mount. 52, and North Amer. 

 Sylv. iii. 132, t. 111. Thuya plicata, Lamb. Pin. ed. 2, 114 

 (not Don). Thuya Menziesii, Dougl. Carr. Conif. 107. Thuya 

 Douglasii, Nutt. Mss. Tliuya Lohhii, hort. Thmja occidentalism var. 

 plicata, hort. ; Hoopes, Evergreens, 321 ; Veitch, Man. 256. 



Habitat. — Alaska, south along the coast ranges and islands of 

 British Columbia, through western Washington Territory and Oregon, 

 and the coast ranges of Northern California to Mendocina County, ex- 

 tending east along the mountains of Washington Territory to the 

 Coeur d'Alene, Bitter Root, and Salmon River Mountains of Idaho 

 and the western slopes of the Rocky Mountains of Northern 

 Montana (Canby and Sargent). 



A large tree, 100-150 feet in height, with a trunk 2^-11^ feet in 

 diameter ; low, rich woods and swamps, less commonly on dry ridges 

 and slopes below 5,200 feet elevation ; common, and reaching its 

 greatest development in western Washington Territory and Oregon ; 

 the large specimens generally hollow. 



Wood very light, soft, not strong, brittle, rather coarse-grained, 

 compact, easily worked, very durable in contact with the soil ; bands 

 of small summer cells thin, dark-coloured, distinct ; medullary rays 

 numerous, obscure ; colour dull brown tinged with red, the thin sap- 

 wood nearly white ; specific gravity, 0'3796 ; ash, 0*17 ; largely used 

 for interior finish, fencing, shingles, in cabinet-making and cooperage, 

 and exclusively by the Indians of the north-west coast in the manu- 

 facture of their canoes (Ch. S. Sargent). 



Thuya gigantea is described under the name of T. Lohhii by some 



