Floristik, Geographie, Systematik etc. — Piianzenchemie. 539 



Auffallend sind die weit kleineren Blüten, die mehr ins Violette spie- 

 lende Farbe; Blüten nur 2-blütige Dolden bildend. Kleiner als der 

 Typus, Haare am unteren Teile 2, am oberen 1 mm lang (beim 

 typischen G. sanguineum aber doppelt so lang)- 



Matouschek (Wien). 



Winkler, H., Eine neue Styuthiola aus Ostafrika. (Rep. Spec. 

 nov. IX. p. 524. 1911.) 



Styuthiola Volkensii H. Winkl. aus Deutsch-Ostafrika ist 

 durch das infolge der weissen Behaarung weiche Aussehen, die 

 vierzeilig und nicht allzu dicht gestellten Blatter und die sehr klei- 

 nen, zarten Blüten ausgezeichnet. W. Herter (Tegel). 



Lloyd. F. E., Carbon dioxide at high pressure and the 

 artificial ripening of persimmons. (Science. XXXIV. p. 

 924—928. Dec. 29, 1911). 



The loss of astringency in persimmons and similar fruits is due 

 to the formation of a colloid complex, of which tannin is one mem- 

 ber, and another carbohydrate the other. A number of substances 

 are capable of hastening the process, but carbon dioxide is peculiar 

 in that, while the loss of astringency is hastened, the remaining 

 changes are relatively held in obeyance, being however hastened 

 as compared with the normal conditions. It was demonstrated that 

 under increased pressure of carbon dioxide the process is hastened, 

 so that with a pressure of 15 pounds the time required was reduced 

 from 6 — 7 days to less than 2 days. 



The role of the carbon dioxide appears to be positive, rather 

 than associated with its inertness. Furthermore the increase in rigi- 

 dity of the tannin masses, usually a slow process, is hastened under 

 increasing pressures of carbon dioxide, but is preceded by a rela- 

 tively brief period, by the completion of non-astringency. It is in- 

 ferred , that the disappearance of insoluble tannin is connected with 

 the coagualation of the associated colloid and that the role of the 

 carbon dioxide is directly or indirectly the cause of this coagulation 

 which proeeeds up to some unknown limit at a rate related to the 

 amount of aeid available. During normal ripening it seems that an 

 enzymatic agent causes the coagulation, and it may be that the 

 chief funetion of the carbon dioxide is in hastening the secretion 

 or action of the responsible enzyme. Moore. 



Lloyd, F. E., The tannin colloid complexes in the fruit 

 of the persimmon, Diospyyos. (Bioch. Bull. I. p. 7—41. pl. 1—3. 

 Sept. 1911.) 



The insoluble nature of tannin in the persimmon as well as the 

 date, is denied. Instead it is contended that the tannin combines 

 with an associated colloid to form an insoluble colloidal complex. 

 The evidence for this is founded upon microscopical, physical and 

 chemical grounds. The tannin mass is shown to have an internal 

 strueture, consisting of a System of canals, spherical Spaces and 

 lacunae of one sort and another. As a result of the swelling of the 

 tannin mass, the canals are broken up and the cavities often take 

 a superficial position on the tannin. mass. The material called the 

 tannin mass is shown to be a tannin colloid complex, the second 

 named term of which appears to be a cellulose mucilage or allied 



