30 Chittenden and Hart — Elastin and the Elastose Bodies. 



becoming turbid when heated, clear again as the solution cools. The 

 product also gives the other reactions common to both proto- and 

 deuteroelastose. 



Analysis of Protoelastose. A 2. 



Percentage composition of ash-free substance. 



16-64 



17-29 



Average. 



7-01 

 16-96 

 21-51 



100-00 



This body, which we prefer to call protoelastose, is apparently iden- 

 tical in composition and reactions with the hemielastin previously de- 

 scribed by Horbaczewski,* and separated by him from a pepsin-acid 

 digestion of elastin, by a method somewhat similar to the one em- 

 ployed by us. 



At first glance, it w'ould appear from Horbaczewski's method of 

 separation, that his hemielastin would consist of a mixture of proto- 

 and deuteroelastose, instead of being identical with the proto body. 

 But the fact that he strongly acidified his digestive mixture with 

 acetic acid, prior to saturating it with salt, explains the matter. 

 Deuteroelastose, which is precipitable from a salt-saturated solution 

 by a little acetic acid, is more or less soluble when excess of the acid 

 is added, and hence by acidifying the mixture sufficiently, the deutero 

 might remain dissolved while the proto would be precipitated by 

 salt from an acid solution, equally as well as from a neutral fluid, 



* Ueber das Verhalten des Elastins bei der Pepsinverdanung. Zeitschrift fiir 

 physiologische Ghemie, Band vi, p. 3,30. 



