ON ROCK PLANTS. 



291 



Arabis. — See " Spring-Bedding Plants." 



Arenaria balearica is a handsome, close-growing species, 

 suitable for creeping over damp stones. It has dark green 

 foliage, and in May and June, when covered with its small 

 white star-like flowers, is very attractive. A. graminifolia grows 

 about 6in. high, and forms grass-like patches, covered during June 

 and July with small white flowers. 



Aster alpinus is a dwarf species, growing 9m. high, and 

 flowering in June and July. The flowers, which are useful for 

 cutting, are bright 

 purple, and upwards 

 of 2in. across. 

 Several varieties are 

 also grown. 



Aubrietia. — See 

 " Spring Bedding 

 Plants." 



Campanula car- 

 patica is suitable 

 either for the rock 

 garden or for the 

 mixed border. It 

 grows ift. high, and 

 produces numerous 

 light blue flowers 

 from May to August. 

 Its variety alba has 

 pure white, flowers, 

 and turbinata, a 

 plant growing about 

 6in. high, has large 

 purplish-blue flowers. 

 C. garganica pro- 

 duces masses of blue flowers with white centres, and is only 

 6in. high. G. F. Wilson is a hybrid growing only 3m. high, 

 and bearing numerous dark blue salver-shaped flowers from 

 June to August. C. pulla is an excellent rock plant, only 

 3in. high, and bearing deep purple drooping flowers from May 

 to 'July. C. pusilla grows 6in. high, and produces its pale blue 

 flowers in abundance from May to September. The variety alba 

 is also grown. 



Cerastium tomentosum. — See "Spring-Bedding Plants." 



Corydalis is a genus of early-flowering plants, suitable either 

 for the rockery or for the open border. They are of easy 

 culture, and may be increased by seeds or division. C. capnoides 

 is a plant growing from i2in. to i8in. high, and bearing white 



u 2 



Fig. 170. — Androsace sarmentosa. 



