1888.] 



Aluminium in certain Vascular Cryptogams. 



127 



with this fact seems to lie in the concentration of the alumina in the 

 gummy matter contained in the latex. It should be remarked here 

 that a little alumina occurs in the ash of some samples of cherry-tree 

 gum and of gum arabic ; whether this substance be constantly present 

 remains to be ascertained. 



Quite recently Mr. H. Toshida (< Chem. Soc. Trans.,' 1887, p. 748) 

 has determined the amount of alumina present in the ash of some 

 grains and seeds, as Glycine Soja, the soy-bean; Phaseolus mungo, 

 the Mung-bean (the var. radiatus) ; rice, wheat, barley, two species of 

 millet and buck-wheat. The highest percentage, 0272, was observed 

 in the ash of Italian millet; the lowest, 0*053, in the ash of the soy- 

 bean. In none of these cases can alumina be regarded as a character- 

 istic ingredient. 



Mr. W. C. Young ('Analyst,' vol. 13, 1888, p. 5) confirms 

 Mr. Yoshida's results as to the occurrence of alumina in wheat. This 

 experimenter found, moreover, that this constituent is intimately asso- 

 ciated with the gluten. In Vienna flour, containing 0"7 per cent, of 

 ash, he found 0'0075 per cent, of phosphate of alumina, which corre- 

 sponds to 0*45 per cent, alumina in the ash. This proportion may be 

 in excess of the truth, for, in separating the alumina strong sodium 

 hydrate solution was boiled in a glass vessel, while no mention is 

 made of a blank analysis having been made to control the result. 



The quantity of alumina found by L'Hote (' Comptes Rendus,' 

 vol. 104, p. 853) in grapes and in wine seems to be too small to be 

 taken into account ; it is a mere trace. 



So far as the materials at one's disposal warrant any definite con- 

 clusions, it may, perhaps, be permissible to say, that aluminium is a 

 characteristic and abundant constituent of the ash of many, if not of 

 all, the species of terrestrial Lycopodia ; that it is absent from Selagi- 

 nella and from a number of other allied vascular cryptogams ; that it 

 is present in notable quantity in at least one species of tree-fern though 

 practically absent from others ; and that it occurs in insignificant 

 amount (like many other elements) in almost every plant in which its 

 presence has been carefully sought for. As to the state of combination 

 in which alumina exists in those plants in which it occurs in mere traces, 

 we have very little information, but in the cereal grains and pulses it 

 is probably in combination with phosphoric acid. In Lycopodia John 

 states that aluminium acetate occurs, Ritthausen speaks of the malate 

 Arosenius of the tartrate. Anyhow it is easy to extract abundance of 

 an organic salt of aluminium by exhausting dried and pulverised 

 Lycoyi odium alpinum with boiling water. So, in some cases, at least, 

 the alumina present in these plants does not exist, as silica does in 

 Equisetum and other highly silicious vegetable structures, in an 

 insoluble form. As to the physiological function, if any, of this 

 element, it is rash to offer an opinion. It is just possible that it may 



VOL. XLIV. K 



