Cfje i^l)obolienbron ^ocietp 
Extract from a Letter from Professor Bayley Balfour to 
Mr. J. C. Williams, dated 21s/ January, 1917. 
Dear Mr. Williams, —In the matter of Rh. caucasicum, I see that Lawson’s 
(Charles Lawson & Sons, prominent nurserymen of Scotland, in the middle of 
last century), give in their Rhododendron Catalogue of 1858 (I have no doubt 
that the preparation of this was the work of Mr. William Gorrie, a noted gardener 
of that date who was their Manager), the following :— 
Rh. caucasicum, Pallas. Native of the Caucasian Mountains, near the 
perpetual snow line. Height 1 ft. to 2 ft. Peat soil, in cool, partly shaded 
situations. 
Caucasicum album. Fine early white. 
Angustifolium. White. 
Involutum. Straw-coloured. 
PiCTUM. Peach colour, much spotted with red. 
Purdie’s white. Shaded with rose. 
Roseum. Rich rose. 
Stamineum. Pale straw-colour. 
Venustum. 
Venustum was first described by David Don, in Sweet’s " British Flower 
Garden,” as a plant of 8 inches high. 
Lawson’s also have the following :— 
” Chrysanthum, fine yellow.” 
McLelland, of Newry, whom Smith, of Newry, succeeded, has in his catalogue 
of 1881-1882, the following :— 
Caucasicum. Yellowish-white (wants shade). 
,, Album. (Cunningham’s white), dwarf. 
,, PicTUM. Pink dark spots.” 
Evidently caucasicum was at that date in the trade a “ yellowish-white.” 
Caucasicum album is too the same as Cunningham’s white. 
ISAAC BAYLEY BALFOUR. 
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