SUPPLEMENT 155 



optimum temperature is less, and at 16 or 37 C. rigor sets in (HossEUS, 

 1903). While the change in expansion in the articulations takes place alter- 

 nately on opposite sides at lower temperatures, at higher temperatures it 

 progresses round in a circle and affects one longitudinal area after another. 



As the temperature gradually increases the leaf apex first of all performs 

 a pendulum movement, and then describes an ellipse whose long axis is parallel 

 to the principal petiole ; finally, the curve becomes a circle (HossEUS, 1903). 



529, 1. i, for perhaps read obviously 

 1. n, for HOSSENS read HOSSEUS 



530, 1. 24, after autonomous movements, read From the fact that tendrils 

 also, when rotated on a klinostat, exhibit regular circumnutatory movements 

 PFEFFER (Phys. II) draws the conclusion that geotropism plays a part in these 

 movements as in those of twiners. According to WORTMANN (1887) the 

 behaviour of tendrils on the klinostat is to be explained otherwise ; the succes- 

 sive bendings towards all sides due to weight render rotating movement impos- 

 sible. Undoubtedly the question requires reinvestigation. 



1. 38, for entirely autonomous, read partly autonomous, partly determined 

 by space relationships in the embryo-sac (MANNING, 1906). 



531, 1. 3, for p. 508, Fig. 336). read II, p. 310, Fig. 202). 



1. 27, after nature, read Further, it has been recently shown (NEUBERT, 

 1902) that the curvatures exhibited by many plumules (Allium) are not purely 

 autonomous, but that geotropism co-operates in their production. . 



532, Lecture XLII is XLI of the 2nd German Edition. 

 1. 46, after in form read of the cell as a whole 



533, 11. 50-1, for The apex . . . with read The head of the arrow indicates 



1. 53, for the withdrawal read the return to the original position of the 

 cilium 



536, 1. 15, after at rest, read According to JENNINGS (1904), however, the 

 streaming movements in Amoeba are carried out in an entirely different 

 manner. Fig. i68a (A) shows Amoeba seen from the side ; it shows that it 

 is only the thin anterior end (from x to a), and not the thick rounded posterior 

 region, that is applied to the substratum. Streamings in the direction of the 

 arrows may be noted through the entire body. On the whole, streaming takes 

 place only in the direction of the forward movement there is no backward 

 streaming of any kind. If a foreign body be stuck to the outer surface of 

 Amoeba one sees it mounting the rear end, and moving forward over the upper 

 surface. When the body has reached a it remains fixed to the substratum, 

 while the protoplasm flows over it, and after it arrives close to the posterior 

 region again, it is sucked up by the stream and carried forward once more. 

 Fig. 168 a (B) shows this movement diagrammatically ; it may be noticed 

 that the particle K remains in the same place from stage 3 to stage 5. Whether 

 JENNINGS'S observations have been confirmed on other hands we do not know, 

 but these observations have been carried out with such minuteness that men- 

 tion of them must not be omitted. 



537, 1. n, for 1868 read 1886 



538, 11. 13-15, delete According to ... FISCHER, 1901). 



1. 38, after details, read If JENNINGS'S observations be correct, then the 

 analogy between an Amoeba and an oil-drop completely fails, and one must 

 admit that amoeboid movement cannot be determined by an alteration of 

 surface tension of the kind indicated. 



539, 1. 53, after weeks read (WART, 1903). 



