1869.] HARDY HERBACEOUS PLANTS. 181 



J. perennis is a taller species, reaching the height of 10 or 12 inches, 

 with stems bent at the base, but afterwards erect, bearing on long 

 stalks compact heads of bright-blue flowers, surrounded at the base 

 with a broad rosette of bracts. The flowers appear in June, July, and 

 August. This is a good useful rock-plant, requiring the same treat- 

 ment as the preceding. It is from the mountains of Central and 

 Southern Europe. 



Phyteuma is one of the most distinct, though not the most showy, 

 of Campanulacese. It is nearly allied to Campanula, but always 

 easily distinguished from it by the curved cylindrical form of the 

 corolla in bud. Though not destitute of beauty of colour, they are 

 not to be recommended for the higher ornamental purposes ; yet all 

 are pretty and decidedly interesting. The list, as given in some 

 catalogues, is probably too long, several of the so-called species proving, 

 in cultivation at least, mere varieties of certain of the best marked 

 forms : some of these will be noticed under their respective relationships. 



P. Tiemisplicericum, a very dwarf species from Switzerland, rarely 

 exceeding 6 inches high, is somewhat tufted in growth, the stems 

 terminating in dense hemispherical heads of bright-blue flowers, which 

 appear in June and July : best adapted for cultivation on rockwork 

 in light rich loam in a moderately dry position. This is a pretty and 

 interesting plant. 



P. humilis is, if possible, more dwarf than the preceding. The 

 blue flowers are produced in globular heads about June and July. It 

 is a tiny interesting plant that should have a warm sheltered place on 

 the rockwork in the same quality of soil as advised for the preceding 

 species. It is found on the Tyrol at great elevations. 



P. orbicular e enjoys a place in the British flora, but is rather rare 

 at home ; it is found, however, plentifully enough in the mountain 

 pastures of central and southern Europe. It varies considerably in 

 height in nature, but in cultivation it averages 1 foot high. The 

 stems are somewhat decumbent at the base, but erect in the upper 

 portion, and terminating in globular heads of violet-coloured flowers, 

 which appear in July and August. It is most suitable for rockwork, 

 but succeeds well in the front lines of mixed borders if the soil is 

 light, rich, and warm, and is always most at home in chalky soils. 



P. Michelii has oval flower-heads, which elongate as the flowers 

 open into cylindrical spikes of bright-blue flowers in July and August. 

 It grows from 6 to 10 inches high, is adapted for culture on either the 

 rockwork or in the mixed border in light rich loam, and is a pretty 

 and distinct species found in various parts of the south of Europe on 

 mountain pastures. P. scorzonerifolium and P. angustissimum difi'er 

 little in cultivation from P. Michelii as regards colour of flower and 



