PINACE^ 503 



paraffin wash made by dissolving 1 lb. of soft soap in two gallons 

 of boiling water, adding two pints of paraffin, stirring well and 

 making up to 16 gallons with clear water before use. Quite 

 recently (in 1922) a bark beetle Phloeosinus thujce, Perris, has 

 been found upon Thuya orientalis and Gupressus pisifera at Kew. 

 Although known to exist on the Continent, it had not previously 

 been recorded in Britain. It is very dark brown or almost black 

 in colour, about i'... in. long, and is related to the ash-bark beetle. 



Key to Thuya. 



I. Main axes of branchlet systems roundish. Glands on foliage 



inconspicuous or absent. 



1. Leaves ending in long fine free points which are parallel 

 to the axis. Under surface of foliage marked with white 

 streaks. Foliage aromatic. — T. plicata. 



2. Leaves ending in short thick rigid triangular points directed 

 outwards at an acute angle. Under-surface of foliage 

 marked with white streaks on the lower half. Foliage not 

 aromatic. — T. japonica. 



3. Leaves as in T. japonica, but more distinctly glaucous 

 beneath. Branches sometimes prostrate. — T. koraiensis. 



II. Main axes of branchlet systems roundish. Foliage marked 



with longitudinal glandular depressions. 



4. Branch systems in vertical planes. Under-surface of 

 foliage pale green. Cones woody with recurved spines. 

 Seeds without wings. — T. orientalis. 



III. Main axes of branchlet systems flattened. Glands on foli- 



age large and conspicuous. 



5. Leaves ending in long fine points parallel to the axis. 

 Under surface of foliage pale green. Foliage aromatic. 

 T. occidentalis. 



IV. Main axes of branchlet systems flattened. Glands absent. 



6. Branchlet systems stout. Foliage with conspicuous white 

 markings beneath. T. dolabrata. 



Thuya dolabrata, Linnaeus. (Fig. 110.) 



HiBA. 



Dolophyllum sji., Salisbury ; Platycladus dolabrata, Spach ; Libocedrus 

 dolabrata, Nelson ; Thujopsis dolabrata, Siebold and Zuccarini ; T. dola- 

 brata, var. australis, Henry. Asunaro ; Asuhi. 



An evergreen tree 40-100 ft. high, or occasionally of shrubby 

 habit. Trunk usually curved at the base and sometimes dividing 

 into two or more branches near the ground. Bark thin, reddish 

 brown, greyish in old or exposed trees, Assuring into long narrow 

 strips, the outer bark sometimes scaling in thin papery layers. 



