155 



of tlie normal respiration, it appears that with each movement 

 of the month-bottom one movement of the flanks takes place dni-in^- 

 these gronps. 



Only the two tirst gronps of the toi)-row set in with a separate; 

 expiration-movement, which is not followed by a movement of the 

 mouth-bottom. For the rest all gronps begin with an expiration, as 

 appears from the fact that the lever descends in the beginning. 

 Dnring the normal respiration the frogs show one tlank-movemenl 

 with some movements of the month-bottom. Dnring the gronps of the 

 Cheyne-Stokes' respiration every movement of the monlh-boltom i.s 

 almost always followed by one tlank-movcment. In this way the 

 frog respires likewise when it is dyspnoeic. 



If the blood of frogs is replaced b}^ normal isotonic solution of 

 Ringer instead of hyperisotonic fluid of Ringkk the mentioned 

 phenomena do not occur. The respiration remains normal, the lense 

 does not become tnrpid. 



A more explicit discussion of the cataract and the Cheyne-Stokes' 

 respiration follows here. 



Cataract. 



In whatever way the fluids of the body of frogs may be made 

 hyj)erisotonic, catai-act occurs always. The cat<iract disappears .ho/ncrer 

 again, when the osmotic pressure of the fiiiids of the hodj/ is made 

 normal a(jain. 



The cataract develops itself very slowly. When after a pei-fusion 

 during 15 or 20 minutes the respiration has stop|)ed already, the 

 surface of the pupil begins only to become a little dim. If then one 

 waits a short time without continuing to drain the circulation- 

 .apparatus, the dimness gradually increases. At last two vertical parallel 

 white sti'ipes are observed on the lense, between which there is a 

 long dark stripe. It makes the impression as if one sees two whiti> 

 walls and between these a deep, dark moat. The direction is usually 

 vertical, sometiines almost vertical. This vertical stripe will correspond 

 to the frontal vertical suture of the lens, as it is de.scribed in Gattp. 

 (Anatomie des Frosches). One often sees white, iliiu lines proceeding 

 in a radiary direction from this vertical line, corresponding to the 

 so-called spokes of the human cataract. It is obvious that the origin 

 of the cataract must be atti-ibuted to a congelation of the albuminous 

 substances in consequence of an increase of the saltconcentration of 

 the fluids of the body. As soon as the osmotic pressure of the fluids 

 of the body decreases again, the pr(K'ess is likewise convei-ted. In 

 my opinion another explanation of the phenomenon is impossible. 



