922 
tion entirely to us, for which we hereby tender him our best thanks, 
and also for the many valuable hints we received from him as 
regards the technicalities of the investigation. 
The allotropy of carbon, as was most natural so to say, was, 
after some experimenting investigations examined Röntgenographi- 
cally, the accompanying photo is a reproduction of the interference- 
figures obtained by letting Cu-rays *) fall upon a bar of compressed 
graphite?) and upon a bar of diamond-powder *). 
From them we notice, qualitatively too, how different the inter- 
ference-figures of these two allotropic forms are, according to the 
quite different crystal-systems (diamond is regular, graphite is mono- 
clinic) in which they are met with. We therefore expect that this 
method will bring light in many cases in which it is doubtful whether 
there is really. allotropy, or where two materials that cannot be 
chemically separated are present side by side. Also in those cases 
in which it is doubtful whether we have to do with the amorphous 
or with the crystalline state, the Röntgen-investigation will, as 
DreBye himself declares, enable us to make the matter clear. 
At the same time we direct the attention to the possibility of 
making a qualitative Röntgen analysis of, say, a mixture or an alloy 
without any loss of material. 
About the particulars of this investigation and the further results 
of it, we hope to be able to say something at some other time. 
Chemistry. — “Amygdalin as nutriment for Aspergillus niger.” 
By Dr. H. J. Warrrman. (Communicated by Prof. J. BÖESKKEN.) 
(Communicated in the meeting of January 27, 1917). 
Periewersenf) has proved that the extract of the cells of Asper- 
gillus niger splits up amygdalin into glucose, benzaldehyde and hy- 
drogen cyanide, whereas the diving mycelium of this species of mould 
behaves in quite a different manner towards amygdalin. 
In the latter case benzaldehyde and hydrogen cyanide are not 
1) For the zCu-line ~ = 1.549 x 10-8. 
*) As made by Moissan and prepared from pure C in the electrical furnace. 
3) Average diameter of the parts 2 à 3 «. 
 H Purtewitscu, Ueber die Spaltung der Glykoside durch die Schimmelpilze. 
Ber. d. deutsch. Bot. Ges. 16, 368 (1898); Also compare : F. Czarek, Biochemie der 
Pflanzen, Ister Band, 2e Aufl. 1913, p. 363—865; F. Larar, Handb. d. techn. 
Mykologie, Bd. IV, Spezielle Morphologie u. Physiologie der Hefen und Schimmel- 
pilze, 1905—07, p. 250—251. 
