153 



tlie cataract had entirely or almost entirel}' disappeared. (Aflei" the 

 frog had remained in water for 2 days not a vestige of the cataract 

 was left). The frog could not in any respect be distinguished from 

 a normal one. 



A second controlexperiment was made in the following manner : 

 The fiog was put in tiie hyperisotonic solution of Ringek, and at 

 the same time a canule was fastened in the dorsal lymph-bag. 

 Slowly water was poured into the lymph-bag thiough this canule. 

 Under these circumstances the fluids of the body did not become 

 hyperisotonic, as tlie water that was withdrawn from the frog 

 along the skin, was replaced again along the lymph-bag. In this 

 way the frogs could remain alive during a week without showing 

 the above mentioned symptoms. Without the drainage ofthelymjth- 

 dorsal-bag the frog dies in the hyperisotonic solution of Ringkk 

 within one day and a half. 



II. Instead of the hyperisotonic solution of Ringkr a hyperisotonic 

 solution of glucose was used (1.387o solution). The frogs behaved 

 in this solution in exactly the same manner. 



III. In a third series of experiments fluid was withdrawn from 

 the frogs by placing them in a dry bottle, and sucking through the 

 latter by means of a water-jet-suctionpump air that had previously 

 passed through lime-tubes. After one day and a half such a. frog 

 iiad desiccated so much as to show the same symptoms as a frog 

 that had been placed in a hyperisotonic fluid. After it had bef^n 

 removed into the water again a complete restoration set in likewise. 



IV. In a fourth series of experiments the blood was replaced 

 from the vena abdominalis by a hyperisotonic solution of Ringkr 

 (with 18 gr. NaCl per L.). When the fluid had sti-eamed through 

 the frog for J 5 to 20 minutes, the same phenomena of coma, 

 passivity and reactionlessness set in. The respiration was then 

 periodical (Cheyne-Stokes' respiration) or stopped entirely. In the 

 latter case the Cheyne-Stokes' respiration could be i-estored by placing 

 the frog for a short time into water. A beginning of cataract could 

 already be observed, when the di'ainage had lasted 15 to 20 minutes. 

 If no further measures were taken, the cataract augmented considerably 

 after the drainage in the course of 10 to 15 minutes. 



All phenomena disappeared likewise in this series of experiments 

 when the frog was removed to water. 



A short description of an experiment may follow here. 



117, o'clock. From the vena abdominalis a frog is drained with 

 a hyperisotonic solution of Ringek duiing 25 minutes. Coma, passivity 



