30 



THE AMERICAN BOTANIST. 



The average date for the opening of the Kennebec at 

 Augusta, Me., is April 6. A general examination of data 

 of this kind, however, will show that the dates so found 

 are too early to represent the advent of spring. As our 

 object is to secure data for a sufficiently large number of 

 stations throughout the United States to enable the con- 

 struction of a chart graphically illustrating the successive 

 advance of spring, the use of this criterion is impossible for 

 lack of material in the warmer regions of the South, where 

 the rivers never freeze. 



The movements of migratory birds or of hibernating 

 animals afford a very unsatisfactory means ot determining 

 the approach of spring. A sufficiently large number of 

 trustworthy observations is not available, and most of 

 the movements recorded are not made for the reasons 

 usually assumed. It is a common error to suppose that 

 animals, by some unknown sense, are able to foresee wea- 

 ther changes, and this vitiates the scientific value of most 

 of the observations recorded. Very often these migrations 

 are simply brought about by the exhaustion of the food 

 supply in a certain region. It is true that many animals 

 possess a superior sense of smell, of taste, or of hearing, 

 perhaps a finer sensitiveness to minute atmospheric dis- 

 turbances, which man has lost by his artificial mode of life 

 (the use of fire, clothing, and shelter) removing him, in a 

 measure, from the direct influence of nature ; but for this 

 loss he is fully compensated by his ability to invent and 

 use the delicate instruments of modern scientific research. 

 The special faculty, seemingly possessed by many animals, 

 of anticipating the seasons is not due to a superior knowl- 

 edge of meteorology, but is the result of experience during 

 past ages, transmitted from one generation to another by 

 inheritance, and producing the fixed habits of life now ob- 

 served. Many curious observations in regard to the first 

 appearance of the ground squirrel, the migration of swal- 

 lows, the far-ofi" song of wild geese hurrying north w^ard, 

 may be found in that old classic. White's Natural History 

 of Selborne, w^hich contains also a model naturalist's cal- 

 endar for that locality. 



