SPIRAL TWINEKS. 17 



(Dicotyledons, continued.) 



Iloya carnosa (Asclepiadaceoe) made several circles in from 16 b. to 22 h. 

 or 24 h. 



Convolvulus major (Convolvulacew) moves against the sun. Plant placed in 

 room with lateral light. 



t . . , 01 .„ f Semicircle, from light in 111. 14 m., to light 



1st circle ... 2h.42m.-i , , „ ' ,.«/*,. 



I 1 h. 28 m. : difference 14 m. 



2nd circle 2 h 47 m •[ Selllit ' irclc » from 1J g ht in lh - 17 nK > to Vl S ht 

 I 1 h. 30 m. : difference 13 m. 



Convolvulus sepium (large-flowered cultivated var.) moves against the sun. 

 Two circles, each in 1 h. 42 m.: difference in semicircle from and to light 14 m. 



Iponueajucunda (Convolvulacea?) moves against the sun, placed in my study, 

 with windows facing the north-east. Weather hot. 



t t ■ i ' i on I Semicircle, from light in 4 h. 30 m., to light 



1st circle a h. 30 m < ° ' ° 



I lh. in. : difference 3 h. 30 m. 



2nd circle 5 h. 20 m. (Late ) . . rt 



ft -i Semicircle, from light m 3 h. oO in., to light 



in afternoon: circle com- > , , „ ' .._ ° _. , 



,_.,.- ,„, , lh. 30 m.: difference 2 h. 20 m. 



pleted at 6 m. 10 h. P.M.J J 



We have here a remarkable instance of the power of light in retarding and 

 hastening the revolving movement. 



Rivea tiliafolia (Convolvulacea;) moves against the sun, and made four revo- 

 lutions in 9 h. ; so that each, on average, was performed in 2 h. 15 m. 



Plumbago rosea (Pluinbaginaeca>) follows the sun. The shoot did not begin 

 to revolve until nearly a yard in height ; it then made a fine circle in 10 b. 45 m. 

 During (lie next few days it continued to move, but irregularly. On August 15th 

 the shoot followed, during a period of 10b. 40m., a long and deeply zigzag course 

 and then made a broad ellipse. The figure thus traced altogether apparently 

 represented three ellipses, each of which averaged 3h. 33 m. for its completion. 



Jasmi num paucijlorum, Bentham (Jasminaceffi), moves against the sun. First 

 circle in 7h. 15 m., second circle rather more quickly. 



Clerodendrum Thomsonii (Verbenacca?) follows the sun. 



h. m. 



April 12, 1st circle 5 45 (shoot very young). 



„ 14, 2nd „ 3 30 



„ 18, semicircle 5 (directly after the plant was shaken in 



„ 19, 3rd circle 3 [being moved). 



„ 20, 4th „ 4 20 



Tecoma jasminoides (Bignoniacea)) moves against sun. 



h. m. 

 March 17, 1st circle 6 30 



„ 19,2nd „ 7 



h. m. 



March 22, 3rd circle 8 30 (very cold 

 „ 24, 4th „ 6 45 [day). 



Tliunbergia alala (Acanthacete) moves against sun. 



h. m. 



April 14, 1st circle 3 20 



„ 18, 2nd „ 2 50 



h. m. 

 April 18, 3rd circle 2 55 [noon). 



„ 18, 4th „ 3 55 (late in al'ter- 



Adhadota cydo.urfolia (Acanthacea?) follows the sun. A young shoot made 







