156 PLANT PHYSIOLOGY 



540, 11. 47-50, delete Since, however, . . . protoplasmic movement. 



541. Lecture XLIII is XLII of the 2nd German Edition. 



543, 11. 38 and 39, for mg. read g. ; for ! read by i g. ; /or J 3 rar^ by ^ g. 



I. 45, delete after 



544, 11. 27-42, for The antherozoids . . . solution, read The spermatozoids 

 of Pteridophyta that have been investigated react to malic acid, as do those of 

 ferns. There is, however, a difference between the three great groups, viz. 

 that the sperms of Equisetaceae are sensitive to malic acid only (SHIBATA, 

 1905 c), whilst in the Filicinae malic acid may be replaced by maleic acid 

 (SHIBATA, 1905 a), and in Lycopodinae fumaric acid may take its place (SHIBATA, 

 1905 b). Sperms of all three divisions are further sensitive to many kations, 

 of which Ca, Sr, and Ba, e.g. in Equisetum, are specially active. In addition 

 to the capacity for responding to the dissociating salts already mentioned, 

 Equisetum has a marked sensitivity to alkaloids. 



In contrast to the uniformity of behaviour of the sperms of Pteridophyta 

 to malic acid, it is very remarkable to note how differently the chief divisions 

 of the Bryophyta behave in this relation. While sugar is the chemotactic 

 substance in the Musci (PFEFFER, 1884), proteid is the chemotactic body in 

 the Hepaticae, e.g. Marchantia (LiDFORS, 1905). 



545, 1. 12, for again halt read now halt in their backward movement. 



II. 13-19, for They are to be ... backwards, read Thus they remain trapped 

 within a definite zone about the centre of the opening of the tube, but their 

 entry into this area is purely accidental, and the stimulus experienced there is 

 not one of attraction but of repulsion induced by the transition to lower con- 

 centrations ; the response consists not as in fern spermatozoids in a turning 

 round movement of the anterior end, a consequent change in direction of the 

 movement, but in locomotion backwards. 



11. 25-7, for hence ROTHERT . . . chemotaxis. read We will, following PFEFFER 

 (Phys. Ill), speak of a topotactic response when the movement consists in a 

 swimming to a definite place after a previous reversion of the long axis, and 

 of a phobic response when it is in the nature of a recoil into a different 

 concentration. 



1. 29, for strophic read topotactic 



1. 45, for apobatic read phobic 



546, 1. i, for apobatic and strophic read phobic and topotactic 

 1. 4, for strophically read topotactically 



1. 5, for apobatic read phobic 



1. 9, for apobatic and strophic read phobic and topotactic 



I. 14, for strophically and apobatically read topotactically and phobically 



II. 15 and 23, for strophic read topotactic 

 11. 18 and 25, for apobatic read phobic 



1. 27, delete from it. 



1. 29, for (1905 b) read (1905) 



I. 46, after chemotaxis. read or the individual ions maybe partly attractive, 

 partly repulsive. 



547, 11. 15-18, delete Further investigations . . . these. 



II. 23-5, for On the other hand . . . 1905 b).] read On the other hand, we 

 have to deal with quite distinct perceptive processes in the chemotactic pheno- 

 mena induced by such kations as K, Ru, Ca, Sr, &c., for solutions of these 

 bodies do not affect the capacity for perception of malic acid. 



Similar statements have been made as to two Bacteria by KNIEP (1906). 

 He has shown that ' bacillus Z ' possesses at least three distinct sensitivities, 



