52 



presence of magnesia in tlie spores.^ However, these same spores did 

 not germinate in the sohition of ammonium acetate used by Molisch 

 and by the writer, but they germinated in various other sohitions, as, 

 for instance, in a 0.5 per cent solution of sodium acetate or of cane 

 sugar containing a small amount of ammonium sulphate. It appears 

 probable, therefore, that a solution containing ammonium acetate as sole 

 organic nutrient is unfavorable for starting in the spores certain proc- 

 esses which render the stored-up magnesium i)hosphate available for 

 the beginning of germination. Perhaps there is formed in the spores 

 the but little soluble magnesium ammonium phosphate when too much 

 ammonia is i^resent in the culture solution. In suitable culture solutions, 

 free of magnesia, the magnesium phosphate stored up in the spores may 

 be economically utilized, and even a considerable mass of mycelium may 

 be produced provided an abundant sowing of spores had taken place. 



CAN IMAGIs^ESIUX SAI.TS BE REPLACED BY BEEYLLIUM SALTS ! 



The attempts to penetrate the mystery of the physiological functions 

 of magnesium naturally have raised the question whether beryllium 

 can perform the functions of magnesium in living cells, since the gen- 

 eral behavior of the compounds of these elements bears a strong chem- 

 ical resemblance to each other. 



In 1890 Sestini - undertook to determine whether wheat could be raised 

 in culture solutions in which magnesium sulphate was replaced by 

 beryllium suliDhate. He sowed the grains in quartz sand which had 

 been treated with hydrochloric acid to remove all mineral impurities, 

 and watered the plants with a culture solution containing beryllium 

 sulphate in place of magnesium sulphate. The i)lants reached a height 

 of 90 to 95 cm., but the control experiment showed the superiority of 

 magnesium over beryllium, as will be seen by the following comparison: 



Wheat grown— 



Xumber of ' Weight of Weight of 

 seeds. ' seeds. single seed. 





1 Grams. Grams. 

 283 , 12.31 0.435 



In the nia'Tiesiuni solution. ........ . .... . 



322 j 15.20 .472 



» 



1 It lias been shoTm Ijy Aso that tlie spores of AspergiUus contain a moderate 

 amount of magnesia. He lias kindlv fumislied the -writer the results of an analysis 

 which yielded for the ash of spores of Aspergillus oryzae the following comj)osition : 



Pe*cent. 



Potassa 45. 96 



Soda 4.13 



Lime 1. 03 



Magnesia 4. 36 



Oxid of iron 4. 91 



Phosphoric acid 39. 64 



Sulphuric acid 2. 00 



Silica 40 



The percentage of ash in the dry matter was 5.15. The fungus had been grown 

 on boiled rice. 



2Le Staz. Agr. Ital., Vol. XX; Ceutralbl. f. Agr. Chem., 1890, p. 464, and 1891, p. 558. 



