OF THE COCOANUT DURING GERMINATION 



343 



On the oppo-site page we give a microphotographic view of 

 edestin crystals from our second preparation .Mthough not the 

 purest, we have selected this preparation for this purpose because 

 its crystals are mostly rhombohedra. These forms rarely occur in 

 abundance in edestin precipitates, octahedra being more commonly 

 obtained. Most of the larger masses among the crystals shown 

 here are " rounded " octahedra ; not in perfect focus because they 

 are thicker than the rhombohedra. The smaller particles consist 

 of globular matter and crystal pieces. 



The crystals given in Fig. 4. were photographed for us by the 

 writer's colleague, Dr. Edward Leaming, who cordially gave us 

 the benefit of his large experience. We wish here again to extend 

 to Dr. Leaming our sincere thanks for his valuable assistance. 



That the substance under discussion is edestin is further shown 

 by the results of analysis. We append our results for nitrogen 

 content, as determined by the Kjeldahl method, calculated for ash- 

 free substance : 



Percentage of Nitrogen in Cocoa Edestin 



Preparations I, 2 and 3 contained amorphous material, possibly some of the 

 gummy matter referred to on page 342, in spite of our efforts to completely remove it. 

 Preparations 4 and 5 were obtained from I and 3 by further treatment with diastase 

 and by recrystallization by dialysis from lo-per-cent. salt solution. They were practi- 

 cally wholly crystalline. 



The above results show that the globulin separated from the 

 cocoanut by the methods here employed is edestin.* 



This same proteid of the cocoanut was examined by Ritt- 

 hausen, t who termed it conglutin without really identifying it with 

 that substance. His analyses gave it a content of nitrogen of 

 1 7.87-1 7.9 1 per cent. Chittenden and Setchell % referred to it by 



*The edestin from barley contains 18.10 per cent. N. That from maize 18.12 

 per cent.; from rye, 18.19 per cent.; wheat, 18.39 P^^ '^^"'- Osborne : Journal of the 

 American Chemical Society, 17 : 547. 1895. 



t Ritthausen : Jahresbericht uber die Fortschritte derThier-Cheraie, 10 : 18. 1880. 



X Chittenden and Setchell : Quoted by Chittenden, Digestive Proteolysis, 32. 1895. 



