470 TRANSACTIOXS, NATURAL HISTORY SOCIETY OF GLASGOW. 



development of the Limpet, was also shown. A cordial vote of 

 thanks was accorded to Dr. Gemmill and Mr. Alex. Gray, curator 

 of the Millport Marine Station, who assisted him. There was a 

 large attendance of members and friends. 



28th February, 1899. 



Mr. Robert Kidston, F.R.S.E., F.G.S., President, in the chair. 



Messrs. Robert Garry, 2 Hill Street, Garnethill ; Alexander 

 Gray, Marine Station, Millport; Robert Henderson, 12 Arma- 

 dale Street; and Alfred J. Steven, 54 Albert Drive, Pollok- 

 shields, were elected as Ordinary Members. 



Mr. James Rankin, M.B., CM., B.Sc, delivered a lecture on 

 " Physiology as a Factor in Evolution," which was illustrated by 

 lantern slides. The lecturer dealt with the theories of Lamarck, 

 Darwin, and Weismann, expressing himself favourably concerning 

 that of Lamarck, who held, inter alia, that new organs appeared 

 in response to a " new need or want which continued to be felt," 

 and also in favour of the hereditary transmission of acquired 

 characters Ho reviewed at length Weismann's theory of the 

 '•continuity of the germ-plasm," and quoted evidence from more 

 recent observation and experiment which showed that the increase 

 of our knowledge of the behaviour of cells under certain conditions 

 tended to discredit that hypothesis. He stated that while it was 

 difficult to prove the transmission of acquired morphological 

 characters, yet in the phenomenon of instinct, or hereditary 

 memory, in the lower animals, we had an example of the trans- 

 mission oi acquired mental traits. Dr. Rankin pointed out that 

 in unicellular animals all the physiological functions necessary 

 to life were carried on, and that these differed in degree only, not 

 in kind, from those of the highest animals, and also that in all 

 probability the qualities shown by the highest animals were 

 present, at least potentially, in the lowest. There is an evolution 

 of the cell as well as of the individual, and in the lowest groups of 

 animals many of the cells remained in an indifferent condition, 

 and were thus extremely plastic, responding readily to physiologi- 

 cal pressure from within and to changes in external conditions. 

 To this plasticity of the cells, to physiological necessity, and to 

 the influence of surroundings the lecturer attributed the radial 



