THE ROCK-GARDEN 91 



to use in more than one combination. A few examples 

 of such groupings of plants will be described, and 

 others given in the lists. 



When I think of the rock-garden plants, and try to 

 bring to mind those that have given me most pleasure 

 for a fair length of time, I think the roll of honour 

 must begin with Lithospermum prostratu7n. There are 

 many that give one as keen a feeling of delight and 

 thankfulness for a week or ten days, or even a little 

 more ; but for steady continuance of beautiful bloom 

 I can think of nothing so full of merit. It is, there- 

 fore, the best of plants for any important rocky knoll, 

 and, as its habit is to trail downwards, it may well go 

 on the very top of some jutting promontory fairly to 

 the front, or be at the top of a bit of almost wall-like 

 rock-work as in the picture. It is neat-looking all the 

 year through, and the deep colour of the small rough 

 leaves sets off the strong pure blue of the flowers. In 

 winter the leaves turn to a kind of black bronze, but 

 never lose their neat appearance, as of a well-fitting 

 ground carpet. The colour blue in the garden, as also 

 in other fields of decorative practice, seems to demand 

 a treatment by contrast as an exception to the generally 

 desirable rule of treatment by harmony. Therefore I 

 do not hesitate to plant near the Lithospermum the 

 brilliant pale yellow Cheiranthus alpinus, and, though 

 I do not find use for many plants with variegated 

 foliage, I like to have in the same group the pretty 

 little Arabis lucida variegata. 



Among a host of plants that are of so eminent a 

 degree of merit that it is almost impossible to give 



