Physiologie. — Palaeontologie. 99 



Oxysäuren erhöhen die Gärungsgeschwindigkeit, und zwar wir- 

 ken schon sehr kleine Mengen (0.02—0.05*^/0) derart, dass die 

 Gärungsgeschwindigkeit um 50— 1007o des ursprünglichen Wertes 

 erhöht wird. Ha r den und Young vermuteten nun, dass diese 

 Erhöhung der Gärgeschwindigkeit auf eine Begünstigung des Wachs- 

 tums zurückzuführen sei. Die quantitativen Versuche der Verff. 

 schliessen diese Ansicht endgültig aus. 



Phosphate wirken in massig saurer Lösung im allgemeinen 

 gärungsfordernd , in neutraler und alkalischer Lösung gärungs- 

 hemmend. Dieser Wirkung auf die Gärung geht, wie aus den 

 Versuchen ersichtlich ist, die Wirkung der Phosphate auf das 

 HefewacTistum nicht parallel. Wie Phosphat wirkt in massig alka- 

 lischer Lösung auch Kaliumacetat. Boas (Weihenstephan). 



Kidston, R. and D. T. Gwynne-Vaughan. On the Fossil 

 Osmundaceae. Part 5. (Trans. Roy. Soc. Edinburgh. L. 2. N^ 16. 

 p. 449—480. pl. 41—44 and 4 text figs. 1914.) 



Five further types are discussed, only two of which are design- 

 ated specifically viz Osmuiidites spitsbergensis (Nath.) from the Ter- 

 tiary of Spitzbergen and O. Carnieri Schuster from an unknown 

 horizon in South Paraguay. The former occurs on a fossil peat 

 former of the detached petioles and laminae, and occasional roots. 

 The Stern structure is unknown. The leaf-bases possessed stipular 

 wings. The petioles are all those of fully developed leaves there 

 being no zones of abortive or scale-leaves. The leaftraces are of 

 the adaxially curved C-shaped Osmundaceous type. In the arran- 

 gement of the sclerench5'^ma of the stipular leaf-base, this species 

 Stands very near to Osmunäa Claytoniana, while the foliage is almost 

 identical with O. regalis. 



Osmundites Carnieri is remarkable for the complete absence of 

 the coating of leaf-bases, the place of which is taken by densely 

 packed adventitious roots. 



The stem was unusually large with an enormous stele 35 mm 

 in diameter, containing 35 free Strands of xylem. The pith was very 

 extensive. A external and internal endoderm is recognised. Roots 

 are also described. This species Stands nearest to Osmundites 

 skidegatensis. 



The other three types, mentioned as O. sp., come from Queens- 

 land and New Zealand and are both very imperfect. 



Agnes Arber (Cambridge). 



Reid, C, The Plauts ofthe Late Glacial Deposits ofthe 

 Lea Valley. (Quart. Journ. Geol. Soc. LXXI. 2. p. 155—161 and 

 plate X. 1916.) 



A long list of determinations of fruits and seeds of an Arctic 

 Flora from several pits in the Lea Valley, includes two new 

 species and several other Angiosperms hitherto unknown in the 

 fossil State. Silene caelata sp. nov. and Linuin Praecursor sp. nov. 

 are founded on seeds, and on the case of the former species, also 

 on~ specimens of the calyx and capsule. Notes on other determinations 

 are added. Agnes Arber (Cambridge). 



Stopes, M. C, An Early Type of the AbietineaeQ) from the 



