GERMINATION OF SEEDS. 587 



accurately known, whether considerable alteration in consti- 

 tution of the vegetation had ever occurred. Samples of 

 earth were so taken as to diminish as far as possible the 

 chance of introduction of seeds by various agents. For 

 collecting earth spots in dense forests devoid of vegetation 

 were chosen, chiefly in such as were known to have formerly 

 been fields or meadows. For comparison samples were 

 taken from primaeval forests. Layers 8cm. deep were re- 

 moved ; this was done twice, and sometinies thrice, at the 

 same spot. The cultures agreed well. In every test of 

 soil formerly field-soil, the majority of seeds that germinated, 

 at times all, were those of field-plants. The results with 

 earth from forests previously meadows, or perennially forests, 

 were analogous. The woods, primaeval ones naturally ex- 

 cepted, had been planted twenty to forty-six years back ; 

 Peter concludes hence that the seeds had remained dor- 

 mant, retaining 'vitality,' throughout these periods. This 

 conclusion is as reliable as any deducible from experiments 

 ot this type, which are permeated with uncertainty. 



Loss of ' vitality ' with age has been recently studied 

 by Burgerstein (]) in seeds of Triticuin {imlgare ?\ Secale 

 cereale, Hordezuji [distickum f) and Avena [saliva ?), aged 

 one to ten years. Hordeuni preserved 'vitality' best, AvenUy 

 TriticuDi and Secale following in order. Of seeds aged ten 

 years, 70 to 90 per cent, germinated in the case of TiHticinu, 

 A vena and Hoi'deiim, i to 2 per cent in that of Secale. 



Concerning the longevity of 1 riticuni, Acton ^ men- 

 tioned that no seed of a sample aged thirty years germinated. 

 This trial was hardly fair, as the mode of storage was not 

 favourable to preservation of ' vitality '. 



Naudin " adduced this year an old experiment of his ; 

 in 1872 he received a bag of dusty earth from the Sahara, 

 from which he reared a Heliantheinuni. hi 1895 he 

 received seeds from Gabon enclosed in earth that weighed 

 less than ikg., but from which he obtained more than 



^ " Changes in the Reserve-material of Wheat on Keeping," Note, Ann. 

 Bot., 7, 1893, 383. 



-"La longevite des graines," etc., Bull. d. I. Soc. Nat. d'Acclini. d. 

 France, Feb., 1897. 



