CALIFORNIA FOR TEE BOTANIST 273 



other activities. If an effort were made, I have no doubt that a very 

 considerable list might be made of plants known to bloom and to fruit 

 only scantily and rarely elsewhere which fruit regularly under the 

 stimulus of the richer and more abundant light which penetrates the 

 dryer atmosphere of the Pacific coast. Liverworts and mosses, " shade- 

 loving " here as elsewhere, fruit abundantly and regularly, but it should 

 be stated that their spores do not always reach perfection because there 

 may not be time enough between the cessation of the rains and the 

 beginning of the really dry season for them to matuxe fully. But, given 

 the necessary minimum of water in soil and air, plants will fruit, crops 

 will come, the more abundantly the more light of suitable composition 

 they receive. And we shall presently see that the rays of the upper half 

 of the spectrum, the violet and the idtra- violet, the ones most absorbed by 

 water and water vapor, whether visible or not, are the ones most stimu- 

 lating to bloom and fruit. Soil fertility, light fertility, and water — 

 these three — and the greatest of these is water. 



VOL. LXXXVI. — 19. 



