Cucurbita maxima and G. JPepo. 107 



p. M., and the rate per minute l*20 cm . This was on a de- 

 creasing temperature, four hours and fifteen minutes after the 

 maximum. The waves of greatest movement were found from 

 2 p. M. until the end of observations, and during a diminishing 

 temperature, The time of least movement was from 11.25 to 

 11.40 A. M., and the rate per minute 0-166 om . This was at 

 the time of maximum temperature. The waves of slowest 

 movement extended from 9 a. m. until 2 P. M., with slight 

 acceleration of movement toward the latter hour. 



Observations commenced with a bright sun and the plant in 

 active condition. At 12 o'clock the leaves drooped, with the 

 thermometer at 34 - 4° # C, and this condition continued until 

 early in the afternoon, when they revived, with decrease of 

 heat. It was during the passive condition of the plant that the 

 slowest movements were observed, the more rapid waves occur- 

 ring with renewed vigor and active condition. The entire 

 dextrorse movement was 143'10 cm ; the sinistrorse 161'4:Q cm , 

 and the ratio was, therefore, as 1 : 112. 



No. 8b. — Observations were resumed at 8 o'clock A. M. of 

 August 17th, and were extended over seven hours and forty- 

 nine minutes. The distance which the tip traveled during this 

 time was 225-00 cm , or at the rate of O^S 0111 per minute. The 

 greatest movement was at the rate of 2 - 60 cm per minute, occur- 

 ring from 3.40 to 3.45 P. m., at the very close of observations, 

 and one hour and forty-five minutes after the maximum of 

 temperature. The waves of most rapid movement were from 

 3.15 to 3.45 p. m. 



Least movement occurred at 10.15 to 10.30 A. M., at the rate 

 of 010 cm per minute. The waves of least motion extended 

 from 8 A. M. until 3.15 P. M., coincident with a rising and 

 maximum temperature. Observations commenced with a 

 bright sun and the plant active. At 11 o'clock A. M., just 

 thirty minutes after the minimum of motion occurred, the 

 leaves were all drooping as a result of excessive transpiration. 

 At 1 o'clock P. M., it was raining, and the normal activity of 

 the plant was restored. This continued until the close of ob- 

 servations. The entire dextrorse action was 1.03 "SO 0111 ; the 

 sinistrorse 121 - 50 om , and the ratio therefore as 1: 1*17. 



No. 8c. — Observations upon No. 8ab were resumed on the 

 17th of August at 5 o'clock p. m. and extended over fifteen 

 hours. Apparently on account of its age, and the time of 

 observation, the entire movements were slow, amounting in the 

 fifteen hours to only 159"00 cm , giving an average rate per min- 

 ute of 0-176 cm . The greatest movement was at 7.12 to 7.28 

 P. M., at the rate of 0*65 cm per minute. The waves of most 

 rapid movement were from 5 to 7.30 P. M., with a slight accele- 

 ration in the morning. Least movement was found at 2.30 to 



