574 Transactions of the American Institute. 



YI. Unsown Crops. 



The sudden and apparently spontaneous appearance of unsown crops 

 on a slight change in the condition of the soil, or of plants entirely 

 new to the neighborhood, when fresh ground is tilled for the first 

 time, is a well-known phenomenon. In particular, farmers are familiar 

 with the fact of the universal appearance of sufficient white or Dutch 

 clover completely to cover the ground when heath-land is first plowed. 

 It is very common also for railway embankments or cuttings to be 

 covered, for the first few years after their construction, with plants 

 indigenous to the country but new to the neighborhood. The usually 

 accepted explanation of these facts is that the soil is everywhere full 

 of buried stores of seeds of all descriptions, which require only 

 favorable circumstances of warmth, light and moisture to bring them 

 to life. In his anniversary address to the Linnean Society, the 

 distinguished president, Mr. Bentham, points out the objections to 

 this theory, which rest rather on circumstantial than on direct evi- 

 dence. Where the seeds are not very small, as in the case with the 

 white clover, they ought to be easily detected by a careful search, if 

 present in sufficient quantities to form a complete crop. Mr. Bentham 

 doubts also whether there is any satisfactory evidence of seeds retain- 

 ing their vitality for any considerable length of time unless kept 

 perfectly dry, as in the case of the grains of wheat preserved in 

 Egyptian mummies ; and calls attention to the rapidity with which 

 large numbers of seeds may be transported to a given spot of earth 

 in an exceedingly short space of time by the agency of birds. The 

 interest and importance of this subject would amply reward a careful 

 series of experiments and observations. 



Prof. John Phin — Dr. Lindley, the botanist, obtained a quantity 

 of matter from the stomach of a man that had been buried in England 

 a great many years ago in an old Danish or Saxon tumulus ; and he 

 found in it several seeds which he identified as the seeds of wild fruit 

 which formerly grew in England ; showing the man had eaten the 

 fruit, and the seeds, although not kept dry, had preserved their vitality, 

 for these seeds were afterward sown and plants grown from them. 



The President — How do you account for the fact that when a forest 

 of pine trees is cut down, oak trees take their place ? 



Prof. John Phin— I do not account for it. A great deal that is 

 said about the age at which seeds will die is untrue. I had at one 

 time a quantity of old seeds that had been put away for fifteen or 

 twenty years, and many of these that all authorities pronounced worth- 

 less grew. Climate has a great deal to do with it. In Egypt or in 



