20 



The Vegetation of the 



above named transactions, but full of printing errors, and, therefore, here- 

 with corrected, will prove that. 



Acer Saccha- 

 rinum 



Crataegus \ 

 Subvillosus \ 



Aesculus \ 

 Glabra ( 



Cerasus < 



Virginiana \ 



Asimina j 

 Tribola 7 



Kobinia ( 



Pseudacacia j 



First Day of 

 Blooming. 



SUM OF DAILY MEAN TEMPERATUEE (CENTIGRADE), 



May 10, 1857 

 Apr. 20, 1859 



S o'O 



oi C 3 



NEGATIVES EXCLUDED. 



Above freezing. 



May 20, 1857 

 Apr. 30, 1859 



39.4 

 327.41522 



526 on 87 days 



88 



155.6642 



97 



452.4 



May 20, 1857 1 155.6 

 Apr. 30, 18591 452.4 



May 25, 1857 

 May 5,1859 



May 31, 1857 

 May 10, 1859 



Jun. 17, 1857 

 May 16, 1859 



263 

 555 



361.2 

 657.5 



471 



767 



646 



642 

 646 



97 



750 „ 102 

 750 „ 103 



848 

 852 



108 

 108 



978 

 962 



115 

 114 



1 degree above 

 freezing. 



443 on 86 days 



447 „ 87 „ 



549 

 562 



96 

 97 



549 

 562 



96 

 97 



652 

 661 



101 

 102 



744 

 758 



107 

 107 



867 



114 

 113 



2 fJegrees above 

 freezing. 



788 

 766 



113 

 113 



Eleven series were calculated in that way as far as ten degrees above 

 freezing point. As the figures diverge more and more, it seems that the 

 sap of our woody plants moves as soon as the temperature rises above 

 freezing point, for there the figures come nearer together. Only Robinia 

 makes an exception, the starting point of which is probably one degree 

 above freezing point. 



This is a Southern tree and at Peoria introduced, but as the observa- 

 tions were made on an individual, standing right near the place of obser- 

 vations, these are the most reliable. 



How much later these plants would have been in bloom in the year 

 1857, when the negative temperatures acted reactive instead of inactive, 

 can be proved by the following table: 



