The Plant Kingdom - 623 



28. Are any of the plants in this phylum impor- sources of economically important materials; 



tant: (a) as a food supply for other organ- (d) from other viewpoints, 

 isms; (b) from a medical viewpoint; (c) as 



FURTHER READINGS 



1. The Plant World, 4th ed., by H. J. Fuller and 2. Botany, 3d ed., by C. L. Wilson and W. E. 



Z. B. Carothers; New York, 1963. Loomis; New York, 1962. 



