i'ig. 53. 



66 OIECUMNUTATION OF SEEDLINGS. Chap. 1 



A filament was next fixed to a cotyledon only i of an inch in 

 height which was illuminated exclusively from aboTe, and as 

 it was' kept in a warm greenhouse, it grew rapidly; and now 

 there could be no doubt about its circumnutation, for it described 

 a figure of 8 as well as two small ellipses in 5^ hours. 



Nephrodium molle (Filices).— A seedling fern of this species 



came up by chance in a flower- 

 pot near its parent. The frond, 

 as yet only slightly lobed, was 

 only -16 of an inch in length and 

 •2 in breadth, and was supported 

 on a rachis as fine as a hair 

 and '23 of an inch in height. A 

 very thin glass filament, which 

 projected fur a length Qf "36 of 

 an inch, was fixed to the end of 

 the frond. The movement was 

 so highly magnified that the 

 figure (Fig. 53) cannot be fully 

 trusted; but the frond was 

 constantly moving in a complex 

 manner, and the bead greatly 

 changed its course eighteen times in the 12 hours of observation. 

 Within half an hour it often returned in a line almost parallel 

 to its former course. The greatest amount of movement occurred 

 between 4 and 6 p.m. The circumnuta- 

 tion of this plant is interesting, because 

 the species in the genus Lygodium are 

 well known to circumnutate conspicuously 

 and to twine round any neighbouring 

 object. 

 Sclaginella Kravmi (?) : Sdaginella, Kraussn (?) (Lycopodiacere). 

 circumnutation of — A very young plant, only '4 of an inch 

 young plant, kept in jn height, had sprung up in a pot in the 

 darkness, triced fr,m ijo^.i^oT^ge. All extremely fine glass fila- 



o.*0 A.M. to lU r M. i i? j 



Oct. 31st. ment was fixed to the end of the frond- 



like stem, and the movement of the bead 

 traced on a horizontal glass. It changed its course several 

 times, as shown in Pig. 54, whilst observed during 13 h. 15 m., 

 and returned at night to a point not far distant from that 

 whence it had started in the morning. There can be no doubt 

 that this little plant circumnutated 



Sephrodivm molle ; circnmnut.ition 

 of very young frond, traced in 

 darkness on horizontal glass, 

 from 9 A M. to 9. P.M. Oct. 30th. 

 Movement of bead magnified 48 

 times. 



Fig. 54. 





