President's Address. 81 



of leaves, not larger tliaii a sliilling above giouud, push thek roots 

 to a distance of a foot to 18 inches in length. This shows the 

 necessity of having the soil deep. Few alpine plants thrive 

 well in shallow soil ; being more easily atfect^d by drought, 

 they require double the attention in watering. A few fiat stones 

 on the surface round the plant prevent evaporation and keep the 

 roots cooler and the soil moist. These are simple matters, 

 but important if you wish to grow well some of these most 

 beautiful plants. They require and must have plenty of water 

 during the growing season, and be kept comparatively dry during 

 the winter. This is what they have in their native hills, but our 

 moist wet winters tend more to kill the plants of this family 

 than any amount of frost. As they are easily damped oil at 

 the period when they are at rest, the beds should be raised con- 

 siderably above the level of the soil, and a quantity of good 

 drainage laid at the bottom. On the top of the drainage I re- 

 commend a mixture of equal quantities of light loam, leaf mould, 

 and coarse river sand, from a foot to 18 inches in depth. 

 Primulas are safe iii winter when covered with snow, as this keeps 

 them dry ; a bell glass, raised an inch or two above the soil to 

 give air, is also useful for throwing off the superabundant moisture ; 

 but where the rare and small varieties are grown, I would advise 

 a duplicate of each si:)ecies or variety to be kept in a cold 

 frame, in case of any accident happening to those left outside 

 during the winter. See also that the lights of the frame are water- 

 tight, as any drip into the inside is very injurious. 



The genus Ayidrosace belongs to this family and contains in- 

 teresting plants ; though as a rule they are more difficult to keep 

 alive in a thriving state than the Primulas. They mostly grow 

 at very high elevations in the mountains of Europe. A number 

 of species have, however, been introduced of late years from the 

 Himalaya. Some of these are free growers, such as A. lanuginosa 

 and sarmenfosa, but all the species are apt to damp off during 

 winter, without a great deal of care on the part of the cultivator. 

 Those I have succeeded best with outside are A. Chanuejasme, 

 carnea, lactea, ohtu^ifoUn, and A. Vital iona; and, although they 

 can all be grown on the rockery during summer, it is wise to 

 keep them in a cool house or frame during winter. I had some 

 luxuriant plants of A. GhanKBJasnie this summer, nearly filling the 

 division marked out for them, but they are now sickly owing to wet 

 broken weather. 



Aretia Vitaliana, a congener of Androsace, and one of the most 

 vigorous, stands the wet weather better than the others. This I 

 always leave outside all winter, and never lose a plant ; but among 



TKANS. 130T. SOC. VUL XVI. F 



