156 



It is obvious that also every other circumstance by which a con- 

 gelation of albuminous substances is caused, can bring about lense- 

 cataract. In my opinion however it is of importance that I have 

 indicated, that a mere increase of the osmotic pressure of the fluids 

 of the body can result in cataract. 



Cheyne- Stokes' respiration . 



The periodical respiration was caused in my experiments by an 

 increase of the osmotic pressui-e of the fluids of the body. The 

 periodical respiration disappeared lil^ewise again as soon as this 

 pressure did not ex.ist any longer. In order to study the origin of 

 the Cheyne-Stokes' respiration more accurately the desiccation of the 

 frogs was continued in a series of experiments so far, that the 

 Cheyne-Stokes' respiration had not yet set in. Thereupon the mouth- 

 bottom was suspended and in a warm room the frog was exposed 

 to further desiccation. Usually the Cheyne-Stokes' respiration slowly 

 set in there in the course of a few hours. During these experiments 

 it appeared that besides a periodicity of the flank-respiration we 

 must distinguish a periodicity of the pharyngeal respiration. In far 

 advanced stages the two periodicities coincide, so that then during 

 the groups movements of both the flanks and the mouth-bottom 

 take place, whilst in the pauses the respiration stops entirely. As 

 a transition to this complete Cheyne-Stokes' res[)iration we find a 

 stage in which the groups are equal to those of the complete Cheyne- 

 Stoke's respii-ation, but during this stage the movements of the 

 mouth-bottom continue. It appears consequently that both ways of 

 respiration are to a certain degree independent of each other, as 

 appears indeed also from the normal respiratory curves. 



According to the examinations of Langendorff the movement of 

 the flanks comes off passively without a contraction of the pectoral 

 muscles. If this is correct, then the movement of the flanks is after 

 all made possible by an active opening of the glottis. With the 

 Cheyne-Stokes' respiration the periodicity of the movement of the 

 flanks is determined by a periodicity of the glottis-muscles. An 

 opening of the glottis is almost constantly followed by a move- 

 ment of the mouth-bottom, this however is not necessary either. The 

 first 2 gi'oups of Fig. 3 set in with an expiration that is brouglit 

 about by an opening of the glottis, which is however not followed 

 by a movement of the mouth-bottom. 



One word more about the cause of the Cheyne-Stokes' respiration 

 in these experiments. As I explained already, this phenomenon 



