338 BOTANICAL GAZETTE [October 



The yield of artificial grains varies exceedingly in different experi- 

 ments. Though two experiments may be performed apparently in 

 exactly the same manner, the number of grains obtained may be vastly 

 different; indeed in some experiments scarcely any are produced. As 

 a rule the first solution extracted from any given preparation gives the 

 best results. 



Chemical tests show that the grains are composed of protein, for 



i 



they respond strongly to all the protein tests such as the xanthoproteic 

 Millon's, etc. In each test the envelope responded just as strongly 

 as the crystal; it consists, therefore, of uncrystallized protein. With 

 other chemical reagents their behavior is that which is to be expected; 

 they are insoluble in water, alcohol, and sodium carbonate, soluble in 

 weak acids and alkalies and in salt solutions. No marked difference 

 could be observed between the solubility of the envelope and that of 

 the crystal. 



Under the action of putrefying bacteria, however, the behavior 

 of the envelope and crystal is occasionally different. In some cases 

 the crystal was dissolved out, leaving the ruptured envelope free; the 

 latter then became flattened out or turned back at the edges. 



In the presence of a disinfectant to prevent putrefaction, the grains 

 usually remain unchanged indefinitely. Sometimes, however, the 

 envelope becomes more or less angular, the angles corresponding to 

 those of the crystal. 



The proteids of other seeds were used in these experiments, but 

 in no case could artificial grains be obtained. Castor bean, hemp, and 

 lupine gave only crystals without envelopes. 



In the case of Bertholletia, however, it seems evident that structures 

 resembling the aleurone grains formed through the activity of the pro- 

 toplasm have been produced in the laboratory. This imitation consists 

 not only in reproducing what is probably the same chemical compound, 

 but also in reproducing the same morphological structure. 



In conclusion I wish to acknowledge my indebtedness to Professor 

 W. J. V. Osterhout, in whose course in plant physiology the original 

 observation was made, and with whose advice the subsequent work was 



done. W. P. ThOMPSOM Unmanl T 1 nwpr <■ h l \t 



