PLANT COMMUNITIES: SEASONAL CHANGES. 331 



with moss and fern. On the partly sunlit slopes the clusters of 

 azalea are radiant with blossoms, while here and there the shad- 

 bush, or service-berry (amelanchier), with its mass of white 

 flower-sprays, overhangs some cliff, and the cockspur thorn 

 (crataegus) vies with it in the profusion of floral display. Near 

 by sheets of water pour themselves unceasingly on the rocks 

 below, scattering spray on the thirsty marchantia. Out from 

 the steep slopes above rise the graceful sprays of the yew (taxus), 



Fig. 272. 

 Spray of kalmia flowers. 



shaded by the towering hemlock spruces. The " walking-fern " 

 here, holding fast above, climbs downward by long graceful 

 strides. 



497. Change in color with the season. But the scene shifts, 

 and while these flowers cast their beauty for the season, others 

 put on their glory. The flowering dogwood spreads its decep- 



