134 The Principles of Vegetable- Gardening 



Trivial injury to the mere integument of the seed may 

 hasten germination. Such injury allows of the absorption of 

 water and the liberation of the germ. The practice of filing and 

 notching of various hard seeds — as of cannas, moonflowers — 

 illustrates this. The soaking and freezing of seeds have similar 

 effects. Sturtevant (3d Rep. N. Y. Exp. Sta. 328) has experi- 

 mented with mechanical injuries to the integuments. A lot of 

 160 Black Wax beans was divided into four lots of 40 each. 

 Lot No. 1 was treated by slightly mutilating the seed -coat opposite 

 the hilum. Lot No. 2 had the coat mutilated in same manner, but 

 was afterwards greased with tallow to retard absorption of mois- 

 ture. Those of Lot No. 3 were not injured. Those of Lot No. 4 

 were not injured but were greased with tallow. The most rapid 

 germinations occurred in the first lot, and the next most rapid 

 in the third lot. The slowest germinations occurred in the fourth 

 and second lots, respectively, showing that an oily coat is a 

 retardative of germination. Following are the figures : 



No. which No. which No. which 

 had germi- had germi- had germi- 





nated in 



nated in 



nated in 





Seeds five days 



seven days 



eight days 



Lot No. 1, 





30 



37 



Lot No. 2, 



mutilated and greased . . 10 



25 



35 



Lot No. 3, 





28 



40 



Lot No. 4, 



not mutilated and greased . 



4 



^ 29 



Tables of longevity of seeds. — Perhaps the most extended and 

 careful series of investigations yet inaugurated for the purpose 

 of determining the vegetative duration of seeds is that under- 

 taken by Messrs. H. E. Strickland, Daubeny, Henslow and Lind- 

 ley, under the auspices of the British Association for the Advance- 

 ment of Science. As many as 288 genera, in 71 orders, were 

 subjected to test in three places, Oxford, Chiswick and Cam- 

 bridge. A Seminarium was instituted at Oxford and placed in 

 the charge of W. H. Baxter. Samples of seeds in sufficient 

 quantity to furnish sets for testing at frequent intervals during 

 a century or more were carefully stored. A summary of results 

 is given in the reports for 1850, p. 160, and 1857, p. 43. 



