Note B — IX.

The method pursued by Messrs. Berkeley and Hoffmann of surrounding the drop of fluid, in which a definite number of spores or yeast globules had been placed, with a pellicle of air, into which the germinating threads might pass and fructify, is perhaps the most satisfactory that has been adopted, though it requires nice manipulation. If carefully managed, the result is irrefragable, though doubts have been cast, without any reason, on their observations.