64 



Anniversary Meeting. 



[Nov. 30 y 



fluids treated as viscous, may be compared (as regards their effects) 

 even when the motions are unstable ; and that if any one of the two- 

 systems is in the critical state separating stability from instability, so- 

 will be the other. 



Last December, Dr. Huggins presented a note on " A Method of 

 Photographing the Solar- Corona without an Eclipse," which had so 

 far proved successful, under the unfavourable circumstances in which 

 he had put it in practice, as to lead to the hope that, under better 

 conditions of atmosphere and elevation, the corona might be photo- 

 graphed, from day to day, with so much accuracy as to preserve a clear 

 record of the changes which it undergoes. And, as the photographs 

 taken during the eclipse at Caroline Island show a condition of the 

 corona, intermediate between those exhibited by Dr. Huggins' photo- 

 graphs at periods antecedent and subsequent to the Caroline Island 

 observations, there is reason to believe that this hope is well based,, 

 and that a new and powerful method of investigation has been placed 

 in the hands of students of solar physics. 



Lord Rayleigh and his sister-in-law, Mrs. Sidgwick, have made a 

 very elaborate determination of the relation between the ohm and the 

 British Association standard of electrical resistance. 



With respect to those branches of knowledge on which I may 

 venture to offer an opinion of my own, I may say that, though our 

 records show much useful and praiseworthy work in biological 

 science, the only event which appears to me to call for special remark 

 is the opening of an attack upon a problem of very great interest, one 

 which, in fact, goes to the root of the question of the fundamental 

 unity of the two great embodiments of life — plants and animals. 



The well-known phenomena presented by many plants, such as the 

 sensitive plant and the sun-dew, our knowledge of which was so 

 vastly extended by Darwin, abundantly prove that the property of 

 irritability, that is, the reaction of a living part, by change of form r 

 upon the application of a stimulus to that part, or to some other part 

 in living continuity with it, is not confined to animals. 



But, in animals, the connexion of the part irritated with that which 

 changes its form is always effected by a continuity of more or less 

 modified protoplasmic substance, and reaction takes place only so long* 

 as that continuity is unimpaired ; while, hitherto, the protoplasmic cell- 

 bodies of plants have appeared to be isolated from one another by the 

 non-protoplasmic cell- walls in which they are inclosed. 



It is as if, in the one case, there was a continuous bond of conduct- 

 ing substance between the point of irritation and the point of contrac- 

 tion ; while, in the other, there was a chain of pellets of protoplasmic 

 substance, each inclosed in a coat of a different nature. 



Now, Mr. Gardiner, in his paper " On the continuity of the Proto- 

 plasm through the Walls of Vegetable Cells," brings forward evidence,. 



