EEPBOBUGTIVE OEGAHS OF PLAKTS. 335 



outer coat of these seeds is exceptionally thick, dense, 

 and resistant to moisture. If this coat be broken by the 

 scratch of a needle the seed will shortly germinate. In a 

 collection of such seeds, kept in water, individuals sprout 

 from time to time. In case of common sorrel (Rumex 

 acetosella), Nobbe & Haenlein found that 10 per cent of 

 the seeds germinated between the 400th and 500th day 

 of keeping in the sprouting apparatus. 



The appearance of strange plants in earth newly 

 thrown out of excavations may be due to the presence of 

 such resistant seed, which, scratched by the friction of 

 the soil in digging, are brought to germination after a 

 long period of rest. Lyell states that seeds of the yellow 

 Nelumbo (water lily) have sprouted after being in the 

 ground for a century, and R. Brown is authentically 

 said to have germinated seeds of a Nelumbo taken by 

 him from Hans Sloane's herbarium, where they had been 

 kept dry for at least 150 years. 



The seeds of wheat usually, for the most part, lose their 

 power of growth after having been kept from three to 

 seven years. Count Sternberg and others are said to 

 have succeeded in germinating wheat taken from an 

 Egyptian mummy, but only after soaking it in oil. 

 Sternberg relates that this ancient wheat manifested no 

 vitality when placed in the soil under ordinary circum- 

 stances, nor even when submitted to the action of acids 

 or other substances which gardeners sometimes employ 

 with a view to promote sprouting. 



Girardin claims to have sprouted beans that were over 

 a century old. It is said that Grimstone with great pains 

 raised peas from a seed taken from a sealed vase found in 

 the sarcophagus of an Egyptian mummy, presented to 

 the British Museum by Sir G. Wilkinson, and estimated 

 to be near 3,000 years old. 



Vilmorin, from his own trials, doubts altogether the 

 authenticity of the " mummy wheat," and it is probable 



