The British Association at Sheffield. 329 
The meeting was opened by Dr. F. F. Blackman, who gave a 
very complete summary of the present state of knowledge and 
speculation on this difficult subject. He dealt with the matter in 
three main sections:— (1) the nature of the reaction (or complex 
of reactions) that constitutes respiration, (2) the extent to which 
the reaction in the cell conforms to the laws of general chemistry 
and (3) the influence upon the progress of the reaction of the 
special medium (protoplasm) in which it takes place. Dr. Blackman 
described some experiments on the effect of starvation which pointed 
to the view that the respiratory output of C0 2 has a double origin, 
partly “ protoplasmic ” and partly the result of oxidation of “ floating ” 
sugar supplies. 
The next communication was from Mr. H. M. Vernon, who 
gave a summary of the possibilities of direct oxidative breakdown 
of sugars and organic acids in animal tissues and mentioned some 
of his own experiments on the respiration of excised organs of 
warm-blooded animals. 
Dr. E. F. Armstrong then spoke about the action of oxidases 
and the strong evidence that some of them are not strictly enzymes 
at all. He showed the oxidative blackening which results when 
Aucuba leaves are exposed to chloroform, toluene and similar 
vapours, and he attributed this effect primarily to these vapours 
being able to pass the semi-permeable protoplasm and set up 
osmotic disturbances in the cell. He suggested that the blackening 
would be accompanied by the absorption of oxygen, and the paper 
that followed by Mr. D. Thoday contained proof that this was so. 
Mr. Thoday dealt with the stimulation of respiration by chloroform, 
and described careful experiments shewing to what extent it affects 
both the intake of oxygen and the output of C0 2 . It seemed 
probable that the chloroform acts by altering the permeability of 
the protoplasm. 
Finally, Professor H. E. Armstrong spoke about the great 
complexity of oxidation in living cells. He held that organic acids 
constituted more important stages in the process than was 
generally believed. 
Another joint meeting (with the Zoologists) was held on 
Friday, when two cytological papers were read before the combined 
sections. In a paper entitled “The New Force, Mitokinetism,” 
Professor Marcus Hartog gave an account of his theories with 
respect to the forces at work during nuclear division. As his views 
have been already published, it will suffice to say here that Professor 
