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XII. Notes made in the Garden of the Horticultural Society upon 

 the rate of growth by plants at different periods of the day. 

 Second Series. — By John Lindley, Ph. D., F. R. S. 



In a previous part of this Volume has been given a detailed ac- 

 count of certain observations upon the growth of plants, and of the 

 inferences which appeared to be deducible from them. Those 

 observations were however made upon plants placed in the at- 

 mosphere of a stove, and therefore it appeared desirable to insti- 

 tute a similar enquiry into the rate of growth in the open air, 

 under the ordinary conditions to which vegetation is exposed in 

 this climate. 



F or this purpose one specimen of each of the following species, 

 viz., the Hop, Vine, Sweet Willow, Scarlet Running Kidney Bean, 

 Tig, Jerusalem Artichoke, and Gourd, was planted in front of a 

 vinery in a sheltered situation favourable for their quiet growth, and 

 their increase in length was noted three times daily. The periods 

 for the observations were fixed at 4 o'clock in the morning so as 

 to ascertain the growth during darkness, at noon so as to obtain 

 the growth in the cooler part of the day, and at 8 P. M., up to 

 which period the plants would have been exposed to the influence 

 of the hottest and driest part of the 24 hours. 



The duty of watching the experiments was intrusted to Mr. 

 Joseph Holmes who examined the plants most carefully for two 

 months, during which time 1011 observations were collected. It 

 has not however appeared necessary to print at length the August 

 observations, because they convey no information beyond what is 

 furnished by the July experiments, as detailed in the following 

 tables. 



