178 Dr. S. J. Lewis. Ultra- Violet Absorption Spectra and 



For the movement of the eye the contraction of the muscle opposing the 

 movement has to be inhibited. In the torsional movement of the leaf it is 

 found that the stimulation of one nerve causes in a contiguous nerve an 

 opposite reaction. The nervous impulses of opposite signs reaching different 

 flanks of the motile organ is thus of importance in the co-ordination of the 

 resulting movement. 



LITERATURE. 



(1) Bayliss, ' Principles of General Physiology,' 1915, pp. 378, 465, 494. 



(2) Bose, J. G, 'Plant Response : (Longmans), p. 40 (1905). 



(3) Bose, J. C, and S. Das, " Petiole Pulvinus Preparation of Mimosa pudica" ' Roy. 



Soc. Proc.,' B, vol. 89, p. 213 (1916). 



(4) Bose J. C, and G. P. Das, "Researches on Growth and Movements in Plants," ' Roy, 



Soc. Proc.,' B, vol. 90, p. 364 (1918). 



(5) Bose, J. C, 'Life Movements of Plants,' vol. 2, p. 597 (1919). 



(6) Bose, J. G, and Guha, 'Life Movements of Plants,' vol. 2, p. 480 (1919). 



(7) Bose, J. C, and G. P. Das, " An Automatic Method for Investigation of Velocity of 



Transmission of Excitation in Mimosa,' 1 'Phil. Trans.,' B, vol. 204, p. 63 (1913), 



(8) Bose, J. G, ' Comparative Electrophysiology,' p. 299 (1907). 



(9) Haberlandt, G., ' Physiological Plant Anatomy' (English Translation), 1914, p. 572. 



The Ultra- Violet Absorption Spectra and the Optical Rotation of 

 the Proteins of Blood Sera. 

 By S. Judd Lewis, D.Sc. (Tubingen), B.Sc. (London), F.I.C. 



(Communicated by Prof. J. N. Collie, F.R.S. Received April 29, 1921.) 



The earlier part of this investigation was described in a paper entitled 

 " The Ultra- Violet Absorption Spectra of Blood Sera," communicated by 

 Sir William Bamsay, K.C.B., to the Royal Society in 1916 and published in 

 the 'Proceedings' (series B, Vol. 89, pp. 327 to 335). 



At the close of the paper, attention was directed to the inadequacy of the 

 sector spectrophotometers then available, and reference was made to one of 

 new design then under construction. In the meantime, a full description of 

 this instrument has been published in a paper entitled " A New Sector Spectro- 

 photometer" by the present writer, in the 'Transactions of the Chemical 

 Society' (1919, vol. 115, pp. 312 to 319), together with figure and diagrams. 

 AVith this instrument completely satisfactory results have been obtained, and 

 with it most of the work now to be described has been done. 



The earlier work had reference to serum as a whole ; and as foreshadowed 



