PHYSICS — NICHOLS. — PHYSIOLOGY — LOEB, RElCHERT. 237 



His work, which has a range from — 190 C. to 400 C, has been continued 

 during the past year and is still in progress. Many of his results have 

 already been published in the Physical Review.* 



(8) The Distribution of Energy in Fluorescence Spectra: 



In earlier work the spectrum of the acetylene flame was used as a stand- 

 ard and fluorescence spectra were compared with it by determining their in- 

 tensities, wave-length by wave-length, in terms of corresponding wave- 

 lengths of the standard spectrum. To derive from such measurements the 

 actual distribution of energy in fluorescence spectra the spectrum of the 

 acetylene flame with that of the light from an ideal black body of known 

 temperature has been compared once for all, thus determining the distribu- 

 tion of energy in the spectrum of the flame. From this a curve was plotted 

 giving reduction factors by means of which any spectrum that has been 

 spectro-photometrically compared with the spectrum of the acetylene flame 

 can be described by means of a curve indicating the actual distribution of 

 energy. The results have been published in the Physical Review. f In con- 

 nection with this work, the value of a unit of absorbed energy in producing 

 fluorescence has likewise been determined, wave-length by wave-length. 



It is hoped at an early day to present for publication an extended memoir 

 describing in full the work on fluorescence and phosphorescence thus far 

 completed by the grantee and various collaborators under grants from the 

 Carnegie Institution of Washington. 



PHYSIOLOGY. 



Loeb, Leo, University of Pennsylvania, Philadelphia, Pennsylvania. Grant 

 No. 582. Study of the toxic action of the poison of Heloderma suspec- 

 tum. (For previous reports see Year Books Nos. 6, 7, and 8.) $500 



The investigation into the toxic action of the venom of Heloderma has 

 been brought to a conclusion and a full account of the results obtained will, 

 it is believed, be ready for publication in the course of the coming winter. 



Reichert, E. T., University of Pennsylvania, Philadelphia, Pennsylvania. 

 Grant No. 632. Study of differentiation and specificity of homologous 

 vital substances. $i,5°° 



In Publication No. 116, entitled "The differentiation and specificity of cor- 

 responding proteins and other vital substances in relation to biological classifi- 

 cation and organic evolution: The crystallography of hemoglobins," it was 

 shown that the hemoglobins of different species of animals differ in chemical 

 constitution, and that these differences are specific in relation to genera, spe- 

 cies, etc. The present research is a supplementary investigation. A number 



* R. C. Gibbs, Physical Review, xxvn and xxxi. 



t Nichols and Merritt, Physical Review, xxx, p. 328. 



