402 SECTIONAL TRANSACTIONS.— I, J. 



Miss E. M. Killick. — Some health hazards from toxic substances in 

 modern industrial civilization (11.30). 



The occasions of exposure to toxic gases and fumes are described, and 

 the possible harmful effects of long-continued exposure to such gases in 

 concentrations too low to cause acute effects are discussed. 



Carbon monoxide is an important example of the type of toxin under 

 consideration since it is a constituent of the exhaust fumes from petrol 

 engines, and also of illuminating gas, in addition to occurring as a by-product 

 in many industrial processes. 



The results of prolonged exposure to very low atmospheric concentrations 

 of carbon monoxide are described under two headings : 



(1) A state of continuing vague ill-health ; 



(2) The development of acclimatisation to the gas. 



The importance of this prolonged exposure to very low concentrations of 

 toxic gases is considered as a factor in reducing the normal reserve capacity 

 of the body to respond to unusual strains. 



Other toxic substances, such as oxides of nitrogen and the fumes of 

 volatile organic solvents, are considered from a similar point of view. 



General Discussion (12.0). 



SECTION J.— PSYCHOLOGY. 



Thursday, September 10. 



Prof. F. A. E. Crew. — A repetition and re-examination of McDougalV s 

 Lamarckian experiment (10. o). 

 In order to be in a position to examine the conclusions which Prof. 

 McDougall has reached, eighteen generations, comprising 1,445 experi- 

 mental and 1,014 control rats, have been trained, and the figures provided 

 by these are compared with those which McDougall derived from twenty-one 

 generations of rats of the same origin. The average number of errors per 

 rat made by the individuals of the tank-trained stock has not decreased with 

 the passing of the generations ; there is no difference whatsoever between 

 the scores of the experimental and control stocks. No evidence was forth- 

 coming which would suggest that rats of the two stocks may be distinguished 

 one from the other by differences in behaviour. Analysis of the pedigrees 

 shows definitely that genetic factors are heavily concerned in the establish- 

 ment of the scores. The parent-offspring correlation is 0-3. A ' quick ' 

 strain has been developed as the result of consistent favourable selection. 

 Amongst my rats there is a great excess of those which tend to leave the 

 tank habitually by one route during the first phase of their training when 

 the light is constant and equal on both sides of the tank and when the 

 platforms are not alive. Furthermore, no fewer than twenty-nine experi- 

 mental and ten control rats, having reacted to the light as light in the second 

 phase of their training when the light was alternating but the platform was 

 not alive, actually learned without receiving a single shock. 



Mr. C. Fox. — Mental heredity (10.45). 



Human mental heredity should be considered independently from 

 physiological heredity. In the latter the inheritance depends on agglomer- 



