Newcomba, Sensitive Life of Asparagus plumosus. 31 



the tip, the longest branch being 3 cm. No secondary branches 

 had unfolded. The apex of the shoot at the time of covering was 

 bent over into the horizontal plane and projected 3.5 cm laterally 

 from the stake about which the stem was twining. The first day 

 after covering, the shoot made 1 complete turn; the second day, 1 more 

 complete turn, and shortened the free tip to 2 cm beyond the stake; the 

 third day, 1 more complete turn, and shortened the free tip to 5 mm 

 with a declension of 45°. The 4th day after covering, the shoot made 

 half a turn and twined no more to the end of the experiment, 

 6 days later. As in former experiments, so in this, the tip was 

 several times brot back to the stake so as to make it possible to 

 twine if circumnutation was taking place. Observations at 15 

 minute intervals for several hours in each of several days disclosed 

 that, as twining ceased, circumnutation ceased. Nutation continued 

 thruout the experiment, but the oscillations became smaller and 

 smaller toward the end. The greatest divergence from the vertical 

 on the second day before the last was 45°, and the declination 

 during the first eight and one-half of the last 27 hours extended 

 from 0° to 15°. During these eight and one-half hours, the tip 

 became vertical 4 times. As in the preceding case, the turns of 

 the spiral became steeper as the shoot neared the end of the 

 twining. The turns of the Spiral made in the light were 53 mm 

 apart, on the 2 last days of twining 60 mm apart, and the last 

 half turn made at the conclusion of twining stretched a vertical 

 hight of 80 mm. (All these turns were made about the same stake, 

 the diameter being about the same thruout.) The total elongation 

 after covering was 53 cm, of which 35 were made after twining 

 ceased, and this section extended in a vertical line. 



It should be said that in the middle of the experiment when 

 the shoot had reached the top of the stake, a cord 2 mm diameter 

 was tied to the stake and fastened taut to a cross bar in the top 

 of the cylinder, thus affording a means for the shoot to twine 

 cven if the possible circumnutation was in a very narrow circuit, 

 The absence of twining in these conditions, as well as my direct 

 observations as before recorded, demonstrates that there was no 

 circumnutation during the last 6 days. 



The regaining of the ability to twine after etiolation had 

 caused its loss was followed in the shoots of the last 2 experiments. 



5) The covering cylinders were removed at midday, and 

 behavior followed in a few observations. Twenty-four hours after 

 exposure to light, both shoots had taken on a pale green color in 

 their apical 10 cm, and both tips were declined about 40° from 

 the vertical, the bent portion having increased from 1.5 and 2 cm 

 when the coverings were removed to 3.5 and 4 cm respectively. 

 Forty-eight hours after exposure to light, the tips had still longer 

 portions declining from the vertical. This increase in length of 

 curved apex was the most noticeable change since uncovering. 

 Ninety-six hours after uncovering, one tip was declined 40°, and 

 the other 70°, with the curved portions 5 cm and 8 cm long 

 respectively. Both tips look as tho ready for twining, but both 



