CANADIAN BUCKTHORN 



Uses, etc. "A small tree rarely exceeding i ft. in diameter 

 by 2 ft. bole. . . Furniture and fancy-work. Said to be suitable 

 for umbrella handles" (57). A wood of firm texture; works 

 hard ; difficult to split. 



Authorities. Kew Guide (57), p. 33. Nordlinger (86), 

 vol. vii. p. 13. 



Colour. A delicate brown marked with fine, close, darker 

 lines, giving the wood the appearance of watered silk. 



Anatomical Characters. As those of Elaeodendron croceum, 

 with the following differences : 



Pores. On the limit of vision with lens, size 5-6 : few 10-25 

 per sq. mm. : easily distinguishable from the cells of the soft- 

 tissue by their lack of colour : scattered thinly and irregularly. 



Rays. Need lens, size 5 : 8-10 per mm. 



Rings. Very clear, though not prominent : boundary, a sharply 

 defined band of brownish, coarse-celled soft-tissue in concen- 

 tric lines of undulating (crenate) contour. 



Pith. ? 



Radial Section. Rays faint pink or purplish flakes on a cleft 

 surface otherwise obscure : rings prominent, the boundaries 

 being close, fine, brown lines. 



Tangential Section. As the Radial, but the ring-boundaries 

 are very prominent, though not broad, dark, granular bands 

 or loops of jagged contour, making a very pretty figure. 



Type specimen authenticated by the Forest Officer to the 

 Government of Natal. This wood should be examined with a 

 microscope. 



No. 42. CANADIAN BUCKTHORN. Rhamnus 

 Purshiana. D.C. 



PLATE IV. FIG. 31. 



Natural Order. Rhamnaceae. 



Alternative Names. Bearberry or wrongly Barberry (2). 

 Sacred-bark Buckthorn : Wild Cherry : Shittim-wood : Cascara 

 sagrada (49). Bearwood (100). 



Sources of Supply. Canada and the United States. 



Physical Characters, etc. Recorded dry- weight 31^-35 J lb. 

 per cu. ft. Hardness Grade 7, compare English Birch. Smell 

 none. Taste not strong but rather nauseous. Burns well with 

 puffs of vapour, heat expels a yellow juice, no particular aroma, 

 embers glow in still air. Solution with water brownish, with 

 alcohol ditto, giving a slight pink ppt. on the addition of potash. 



Grain. Fine, dense and compact. Surface lustrous in all 

 sections. 



Bark. Of a " bluish-grey colour mottled with whitish, quite 



49 E 



