586 



SCIENCE 



[N. S. Vol. XLI. No. 1059 



he loses in tlie urine, only in less amount. The 

 frog does the whole more easily. When sitting 

 in the water it not only absorbs water to supply 

 its needs, but loses at the same time the non- 

 volatile products of its daily metabolism (these 

 diffuse into the water from the skin exactly as 

 the same substances in the mammal diffuse 

 from the kidney cells into the water running 

 down the uriniferous tubules). As I have so 

 frequently insisted, solutions are not absorbed 

 or secretions given off " as such." While a 

 secretion of water and of dissolved substances 

 may occur in the same direction, they may 

 quite as easily take opposite ones. These con- 

 siderations make it apparent why on a priori 

 grounds alone the frog (and other amphibia) 

 should he able to tolerate a loss of hidney 

 function better than land animals. 



Experiment has justified the conclusion. I 

 tried originally to bring proof in this direction 

 by cutting the kidneys out of frogs. The 

 operation is not only difficult, but fails because 

 of the anatomical peculiarities which char- 

 acterize the circulation in these animals. 

 Since the venous blood returning from the legs 

 passes through the kidneys, their excision is 

 followed by an edema of the hind legs. To 

 escape this effect and yet to exclude the ex- 

 ternal function of the kidneys, the ureters were 

 therefore tied. Under aseptic precautions a 

 series of frogs were operated upon through the 

 flanks and the ureters isolated. They were 

 tied with a iirst ligature close to the kidney and 

 with a second as near the bladder as possible, 

 the connecting segment of ureter being cut out. 

 These animals have now lived since January 8 

 of this year and are perfectly normal. 



My technical assistant, Josef Kupka, showed 

 me how to keep these animals in excellent con- 

 dition. They are housed in glass boxes heavily 

 padded with moist moss. Inverted porcelain 

 dishes with side openings permit them to hide. 

 A shallow enamel pan always filled with fresh 

 water is placed at one end of each cage. Every 

 few days the frogs are fed live meal worms, 

 which they devour ravenously. The wounds 

 heal completely two weeks after the operation. 

 At the present writing the animals thus oper- 

 ated are livelier and in better physical condi- 



tion than the winter frogs comprising the stock 

 from which they were chosen. 



The kidneys of the frog after ureteral liga- 

 tion seem to suffer but slight if any change. 

 What has been observed will be discussed at 

 another time. 



These experiments prove that frogs may live 

 for weehs after complete suppression of external 

 hidney function. If the explanation of why 

 this is possible in the frog is accepted as cor- 

 rect, it not only gives scientific support to long- 

 established empirical clinical practises, but 

 emphasizes the importance of a closer analysis 

 of the conditions which may improve qualita- 

 tively or quantitatively the matter of absorp- 

 tion and secretion of water and absorption 

 and secretion of food and the products of 

 metabolism through the skin and bowel in the 

 patient suffering from an inadequate kidney 

 function. Martin H. Fischer 



EicHBEKG Laboratory of Physiology, 

 University of Cincinnati 



SOCIETIES AND ACADEMIES 



THK CHICAGO ACADEMY OP SCIENCES 



The annual meeting of the Chicago Academy of 

 Sciences, held January 12 at the Academy building 

 in Lincoln Park, Chicago, was an occasion of spe- 

 cial interest. The chief speaker was Dr. Albert A. 

 Michelson, of the University of Chicago, who pre- 

 sented in simple, unteehnical language the results 

 of his remarkable studies on the rigidity of the 

 earth. Dr. T. C. Chamberlin reviewed the history 

 of the academy during the past eighteen years, dur- 

 ing which time he had been president, and the fol- 

 lowing ofSeers for the coming year were elected: 



Professor John M. Coulter, President. 



Professor Henry Crew, First Vice-president. 



Dr. Stuart Weller, Second Vice-president. 



Dr. Wallace W. Atwood, Secretary. 



Mr. Henry S. Henschen, Treasurer. 



Mr. La Verne Noyes, president of the board of 

 trustees, spoke encouragingly of the present and 

 future work in the museum. Mr. Noyes is espe- 

 cially interested in the construction of habitat 

 groups illustrating the natural history of Chicago 

 and vicinity, and through his personal supervision 

 and generosity a remarkable series of forty-one 

 new groups was opened for inspection at the close 

 of the business meeting. Dr. Wallace W. Atwood, 

 of Harvard University, who has held the secretary- 

 ship of the academy during the last few years, and 

 been associated with the academy boards in the or- 



