1880.] On the Chemical Composition of Aleur one- Grains. 391 



principally consist is a vitellin, and possibly the formation of a preci- 

 pitate which takes place during the saturation of the 10 per cent. 

 NaCl solution may be attributed to a conversion of a part at least of 

 the vitellin into a myosin. 



In the course of my observations it became evident that alcohol, 

 contrary to the generally received opinion, does not render the vege- 

 table globulins insoluble in solutions of neutral salts.* All the above- 

 mentioned reactions are given by aleurone-grains which have been in 

 alcohol for a very considerable time. The grains of Ricinus, for 

 example, after having been in absolute alcohol for more than a year, 

 give the same reactions as fresh ones. This is true of the globulins, 

 not only whilst they exist in the form of aleurone-grains, but after 

 their extraction ; thus, the precipitate obtained by diluting a 10 per 

 cent. NaCl extract of Ricinus seeds was quite soluble in 10 per cent. 

 NaCl solution after having been for a month in alcohol. 



The action of alcohol upon the crystalloids of Ricinus is remarkable 

 in that it renders them readily soluble in saturated NaCI or MgS0 4 

 solution. That they are otherwise quite insoluble in these fluids is 

 proved by the fact that I have kept quantities of crystalloids in excess 

 of the saturated solutions for months ; if some of these be treated for 

 a few minutes with alcohol, they can be seen under the microscope to 

 dissolve at once in these solutions. It is of interest to note that if, 

 after treatment with alcohol, the crystalloids be washed with water, 

 they lose their solubility in these saturated salt solutions, and that they 

 only regain it after being again treated with alcohol. Alcohol appears, 

 in this case, to convert a substance which is insoluble in saturated 

 salt solutions into one which is soluble, that is, a myosin substance 

 into a vitellin substance ; and, from the foregoing facts, it seems that 

 this conversion is closely connected with the removal of water from 

 the substance. 



These observations led me to investigate the crystalloids of a variety 

 of plants with these reagents, and by the kindness of Dr. A. F. W. 

 Schimper, of Strassburg, who has closely studied the subject (" Unters. 

 lib. die Proteinkrystalloide," 1879), I was enabled to experiment upon 

 the crystalloids which Professor Drechsel has succeeded in producing 

 artificially from the proteids in the seeds of Bertholletia (Brazil nut) 

 and of the pumpkin (Cucurbita) (" Journal f. Prakt. Chem.," 1879). 



The results may be briefly stated as foJlows : — 



A. Crystalloids insoluble in NaCl or MgS0 4 solution ; Musa HilKi, 

 Musa JEnsete. 



B. Partially soluble in NaCl or MgS0 4 solution; Sparganium 

 ramosum. 



* Radlkofer (" TJeb. Krystalle proteinartiger Korper," ] 859) has already pointed 

 out that alcohol does not cause the coagulation of the crystalloids of Ricinus, of 

 Bertholletia, and of Sparganium ramosum. 



2 f 2 



