Cucurbita maxima and C. Pepo. 103 



least activity was from 9.50 A. M. to 3.50 P. M. The absolute 

 minimum of motion was from 2.10 to 3.50 P. M., amounting to 

 0*031 om per minute. It occurred on a decreasing tempera- 

 ture, five hours and fifty minutes after the maximum tempera- 

 ture had passed. During this time the sun was shining brightly, 

 though its effect was somewhat modified bj^ numerous clouds. 

 From twelve o'clock to the close of observations, during the 

 time of least activity, the leaves and flowers were all depressed 

 from the effects of the heat. The movements as first recorded 

 were to the left, but after two courses changed to the right. 

 The total dextrorse movement was 184 om ; the sinistrorse 

 47"S0 cm . tnus giving a ratio of 1 : 2*6. 



Tendril No. 5. 



No. 5a. — This tendril was selected August 13th at 4 P. M., as 

 soon as it had straightened out from the bud, and very nearly 

 the first nutations were obtained. Observations were inter- 

 rupted after a few hours and not resumed until the next morn- 

 ing. The entire length of movement was 107 - 60 cm , occupy- 

 ing four hours and thirty minutes, thus giving 0*39 cm as the 

 average rate per minute. The greatest movement was at the 

 rate of 144 cm per minute and occurred from 4 to 4.05 P. M., 

 at the very commencement of action and observation. The 

 time of greatest movements occurred from 4 to 4.35 P. M., and 

 again from 5.30 to 7 P. M., coincident with decreasing tempera- 

 ture. 



Least activity was noticed at 7.55 to 8.10, when the tip moved 

 at the rate of 0'13 cm per minute. This occurred at the time 

 of lowest observed temperature, the thermometer standing a 21° 

 C. The time of best movements was found to extend from 4.35 

 to 5.30, and again from 7 to 8.50 P. m., when the observations 

 ceased. 



At the commencement of observations, the sun was shining 

 brightly and its effect was sufficiently strong to cause a de- 

 pression of all the leaves and flowers. Shortly after observa- 

 tions ceased, the sky became cloudy, and at nine o'clock there 

 was a heavy shower, which revived the plant and brought all 

 the parts once more into active condition. The first recorded 

 movement was to the left, action in this direction predominat- 

 ing during the time of observation. The entire movement to 

 the right was 18-80 cm ; that to the left was 88-80 cm , giving a 

 ratio of 1 : 472. 



No. bb-c. — This tendril was the same as 5a, observations 

 upon which were interrupted at 8.30 P. M., August 13th, and 

 resumed the next morning at 8 o'clock, continuing through the 

 14th and loth. During the night the arm was quite active, 

 and in the morning showed no tendency whatever to discon- 



