QUARTERLY CHRONICLE. 35 



this solution, after having- been heated to 140° C, is exa- 

 mined microscopicallvj the minute germs Avhich it always 

 contains are seen to be still browner than the fluid, and they 

 never germinate. The solution, consequently, in this con- 

 dition is fitted for further experiment with the spores of 

 various fungi. When these have been introduced the tubes 

 should be placed in a bath at from 30° to 40° C, which should 

 be maintained as nearly as possible uniform. In three or four 

 days yeast will be abundantly formed. The spores of Peni- 

 cillium glaucum appear to afford the most certain and copious 

 results, whilst from those of Mucor, Aspergillus, Arthro- 

 botrys, VerticilUum, and Acremoniiim, it is more diflicult to 

 produce yeast in pure sugar water, especially when the 

 spores are at all old. But the addition of a little fruit-juice 

 at once promotes its production. 



The results at a lower temperature are widely different. 

 Even at the temperature of 25° C. an extraordinary quantity 

 of thick germ-filaments are produced, which, as it were, ab- 

 sorb the entire plasma for their own nutrition, and conse- 

 quently few or no granules are afforded. 



In similar manner it would seem that the yeast-cells may 

 be produced from the Yibriones of a putrescent fluid in the 

 course of forty-eight hours. In this experiment care must be 

 taken that too great a quantity of the Vibrio-germs slioidd 

 not be introduced into the sugar solution. Vice versa, on 

 the addition of yeast-cells to a putrescent animal fluid, the 

 production of Yibrio-germs from them may be witnessed. 



In the few observations appended to this valuable commu- 

 nication by Madame Liiders Professor Hensen gives his 

 testimony as to the patience, perseverance, and care with 

 which the experiments were performed, many of which were 

 repeated by himself with similar results. He remarks also 

 upon the fact, deducible from all recorded observations on 

 the subject, that the germination of fungi, the formation of 

 yeast-cells, and of Vibrios, never proceed at one and the same 

 time and spot, but are always successive — one form disappear- 

 ing as the other comes upon the stage. In illustration of this 

 general law he cites a valuable paper by Oehl and Cantoni,* 

 who, in their researches with an extract of beans, invariably 

 observed, after the disappearance of the Vibrio-fauna, the en- 

 trance of a flora, eventually passing into the development of 

 fungi. 



6. A Contribution toivards the Knowledge of the '' SaccuU 

 of Miescher." By Professor W. Manz. — Miescher's Sacculi 



* ' Aunali uuiversali,' vol. cxcvi, p. 352, '• Ricclierclie siillo sviluppo degli 

 Infusori." 



