330 DESCRIPTIONS OF THE SHRUBS 



we have to consider, retain the juvenile form ; others have both forms on 

 different parts of tlie i lants ; while still others have only the scale leaves. 

 The two genera above given can be surely separated only by an examina- 

 tion of the cones ; and small plants rarely show these. The cones of 

 Thuja are elongated with 8 to 12 lapping scales, and those of Chamie- 

 cyparis are nearly globular of G to 10 scales touching edge to edge. All 

 these cones mature in one season and are small, always less than an 

 inch and usually ^ to | inch in diameter. 



When the scale leaves appear, the branches on both genera so form as 

 to produce flat fan-like growths. Tliis plan of branching, called 2-ranked, 

 separates the Arborvit?e from all the Junipers — Juniperus — and the 

 true Cypresses — Cupressus. 



These plants will be found in books and nursery catalogues under the 

 names of Thuja, Thuydpsis, Biota, Cuprdssus, Chamsecyparis, and 

 Retin6spora ; but they will not all be spelled as here given. The first 

 is often spelled Thtiia and Thuya in modern books, and the last 

 Retinispora. 



KEY — BASED ON THE CONES — EOR SEPARATING 

 THE DWARF FORMS OF THUJA AND CHAMiE- 

 CYPARIS 



* Cones elongated,, with elongated lapping scales, Thuja. (A.) 



A. Cone scales thin, 8-10 in number ; cones J inch long and some- 

 what pendulous. Common Arborvit.e (588) — Thuja occi- 

 dentalis. 



A. Cone scales G-8, thickened, and having a horn-like process on 

 each. Cones nearly erect, and about an inch long. Eastern 

 or Chinese Arborvit.e (580) — Thuja orientalis. 



A. Cone scales 8-10, thickened and reflexed, witli 3-5 seeds under 

 each ; cones somewhat pendulous. Dwarf Dolabrata Arbor- 

 viT^ (590) — Thuja (Thuyopsis) dolabrata. 



* Cones globular, of 6-12 scales, which touch edge to edge. Chamrc- 



cyparis. (B.) 



B. Cones about I inch in diameter, of 8-10 brown scales.. Hinoki 

 Retinospora — Chamaecyparis obttisa. 



B. Cones about i inch in diameter, of 10-12 brown scales. Sawara 

 Retinospora — Chamaicyparis pisffera. 



B. Cones about ^ inch in diameter, of 8 reddish brown scales. Law- 

 son's Cypress (5*.»1) — Chamaecyparis Lawsoniiina. 



B. Cones about J inch in diameter, of G glaucous-green or purplish 

 scales. White Cedar — Chamaecyparis thyoides (C. spha- 

 roidea). 



