110 D. P. Penhallow — Tendril Movements in 



was thus as 1 : 1*29. The hours of night were reckoned from 

 7 P. M. to 7 a. :u., consequently those of clay from 7 A. M. to 

 7 P. M. The average rate of growth for the night was found 

 to be 0'49 cm per hour, that for the day 0'633 cra , or as 1 : 1-29. 



The hourly variations were much more regular when the 

 temperature was low, or, under a high temperature when, ow- 

 ing to the moisture in the air, transpiration was not excessive 

 and the normal tension of the tissues was maintained. When, 

 however, under conditions of high temperature and dry atmo- 

 sphere, transpiration was great and all the leaves, flowers and 

 terminal bud drooped in consequence of the resulting release 

 of tension, then the variations became more irregular. We 

 find then, so far as this goes, that while growth is continued 

 through the night, it is much greater during the clay ; that the 

 higher the temperature the more rapid the growth ; that exces- 

 sive transpiration interferes with regularity in growth and even 

 retards it. 



Growth of the Squash. 



To determine the rate of growth in the squash, and the mod- 

 ifying conditions, care was taken to select a young fruit without 

 blemish, and to preserve the vine upon which it grew from 

 injury. One of Fairbanks' platform scales was drawn close to 

 the vine and securely fixed in position. Upon it was then 

 placed a wooden cradle adapted to the form of the squash. 

 The latter was allowed to lie upon a layer of hay to preserve 

 it from injury. The vine was carefully drawn up and allowed 

 to pass by one end of the cradle. The whole arrangement was 

 carefully balanced before and after placing the squash, and the 

 latter was found to weigh just 61 pounds, at the beginning of 

 the experiment. The weight was taken every day at one 

 o'clock P. m. The following table will show the results. 



Growth of the Squash. 



Date. 



Mean temp. 



Total weight. 



Daily increase, 



Aug. 9, 



24-0° 



c. 



61 



o-o 



10, 



25-1 





64 



3-0 



11, 



23-1 





67 



3-0 



12, 



23-9 





72-5 



5-5 



13, 



23-9 





75-5 



3-0 



14, 



24-9 





77-5 



2-0 



15, 



25-9 





80-0 



2-5 



16, 



24*2 





83-0 



3-0 



17, 



21-7 





86-0 



3-0 



18, 



19-3 





88-5 



2-5 



Totals, 



235-9 



755-0 



27-5 



Means, 



23-59° 



c. 



75-5 



3-05 



