XXIV PROCEEDINGS OF THE 



prehensive theory having a direct bearing on the doctrine of 

 evolution— the theory that there is always movement in pro- 

 gress, and its amplitude, or direction, or both, have only to be 

 thus modified for the good of the plant in relation to internal 

 or external stimuli. Vines, although he describes circunmuta- 

 tion and all the other movements mentioned by Darwin, never 

 once refers to this theory, but seems to go a step back and 

 refer all movements directly to the irritability of the proto- 

 plasm in the cells when acted on by stimuli internal or 

 external, without calling in the aid of this intermediate 

 movement of circunmutation. Again, Darwin regards twining 

 as an amplification of the ordinary movement of circunmutation, 

 but points out in his work On the Movements and Habits of 

 Climbling Plants that the twiner does not circumnutate and 

 turn at the same rate. This difference of rate he ascribes to 

 the continued disturbance of the impelling force by the arrest- 

 ment of the movements at successive points through friction. 

 Vines, on the other hand, while agreeing that circunmutation 

 may contribute to the twining movement, takes into account 

 the sensitiveness of the stein to contact. Mr. King minutely 

 described Darwin's experiments on the sensitiveness of radicles 

 to external stimuli, and expressed his concurrence in the view 

 that the curvature produced by artificial stimuli must be 

 regarded as a pathological rather than a natural phenomenon. 

 The question of the nature of the force behind the mechanism 

 of movement is fully discussed by Vines but not by Darwin. 

 A single remark by the latter, however, seems to indicate a 

 general agreement. The chemical decompositions and combina- 

 tions which are constantly taking place in the protoplasm of 

 the living cell result in the liberation of energy which manifests 

 itself in the movement. Of course, behind all this there is 

 the unexplained mystery of life itself. In conclusion, Mr. King 

 described the experiments made by Knight in LSOtJ to determine 

 the force of gravity on the geotropic movement of growing 

 radicles. 



The following papers were also read : 



"The Food of Fishes," by Mr. David Robertson, F.L.S., F.G.S.* 

 "On the Oral Apparatus of the larva of Wonnaldia, a genus 

 of Trichojitcra," by Mr. Kenneth J. Morton. t 



29th March, 1SS7. 



Dr. James Stirton, F.L.S., President, in the Chair. 



Messrs. John M'Cabe, M.A., 47 Quarry Street, Hamilton, John 

 Clark, Gushetfaulds Railway Dcpof, and John Armour, 58 

 Hospital Street, were elected Ordinary Members. 



, * Transactions, vol. ii., p. 146., .JIbid., p. 115. 



