FIG. 196. Two plants of a rock-rose (Helianthemum), showing the effect of low 
ground and alpine conditions. The low-ground plant (a) shows an open habit, 
and elongated stems with comparatively large and well-separated leaves. The 
same plant in alpine conditions is drawn to the same scale in ft, and magnified in 
c, the very short and compact habit being in striking contrast with that of the low- 
ground form. After BONNIER. 
