[Chap. XXXIV GROWTH, DORMANCY, GERMINATION OF SEEDS 399 



studies of the nuclei of the cells after these three different treatments. 

 These facts seem to indicate that prolonged storage of seeds results in the 

 breakdown of nuclear organization and the mechanism of heredity. This 

 answer has more experimental results to commend it than the preceding 

 ones, and it seems to be the best one at the moment. 



Caution. Anyone interested in the preparation, storage, or germina- 

 tion of particular kinds of seeds should not depend wholly on the 

 generalized statements concerning the best methods. There is now a con- 

 siderable body of data available regarding these techniques, and it 

 should be searched before attempting to prepare, store, or plant the 

 seeds of valuable plants. 



Another precaution may also save time and disappointment. One 

 should first of all be sure that the seeds have embrvos inside them, 

 since there are seeds that look perfectlv normal on the outside but 

 lack the most essential part of a seed. One should also make sure that 

 the parts inside the seed coat are in a healthy condition, that they have 

 not become infected bv bacteria and fungi, or infested by insect larvae. 



The references below will be helpful in seeking further details about 

 seeds, their preservation, and their germination. 



REFERENCES 



Crocker, William. Mechanics of dormancy in seeds. Amer. Jour. Bot. 3:99-120. 



1916. 

 Crocker, William. Life-span of seeds. Bot. Rev. 4:235-274. 1938. 

 Davis, W. E. The development of dormancy in seeds of cocklebur (Xan- 



thiitm). Amer. Jow: Bot. 17:77-87. 1930. 

 Ives, S. A. Maturation and germination of seeds of Ilex opaca. Bot. Gaz. 76: 



60-77. 1933. 

 Knudson, Lewis. Nonsymbiotic germination of orchid seeds. Bot. Gaz. 73:1-25. 



1922. 

 Meyer, B. S., and D. B. Anderson. Plant Physiology. D. Van Nostrand Com- 

 pany, Inc. 1939. 

 Miller, E. C. Plant Physiology. 2nd ed. McGraw-Hill Book Company, Inc. 



1938. 

 Shaw, Margaret F. A microchemical study of the fruit coat of Nelumbo lutea. 



Amer. Jour. Bot. 16:259-276. Plates XIX and XX. 1929. 

 Contributions from the Boyce Thompson Institute, 1926 to the present. 



