In these experiments the apiculated ferment appeared sometimes, but much less frequently than _saccharomyces pastorianus_. We also met with the ellipsoidal ferment. We should probably have a greater variety of ferments if our experiments could be conducted in the open air, but insects and particles of dust of all kinds brought by the wind render experiments under such conditions difficult and untrustworthy. In a laboratory we have not these difficulties to contend against, but, unfortunately, the operations ordinarily carried on there cause the results of our experiments to be of a less general character than they would be if obtained in free contact with country air. Footnote 100: [A rather serious clerical error appears to have here crept into the original, for on referring to Plate I. and the letterpress descriptive of No. 7 (p. 5), we find it applies to a very formidable species of diseased ferment, whereas the author is here speaking of an amorphous deposit, harmless in character, and more or less associated with all yeasts. Doubtless No. 7 should stand No. 6, see p. 6.—D. C. R.] Footnote 101: [We would here call the reader’s attention to the following extract from Dr. Graham’s appreciative review of this work in “Nature,” January 11th, 1877. He says: “M. Pasteur seems to be in error in stating (p. 190, Fr. ed.) that the bottom yeast may be distinguished by being less spherical than top yeast. It is true that in London and Edinburgh yeast, the cells will be found usually round; hard water, however, such as that at Burton, or artificially made so, yields yeast in which the cells are distinctly ovoid in appearance, resembling very closely Bavarian bottom yeast.”—D. C. R.] Footnote 102: [43° F. to 46° F. or 59° F. to 68° F.] Footnote 103: [On this point again Dr. Graham expresses some dissent (“Nature,” loc. cit.): “Here surely M. Pasteur must be thinking rather of the inferior products of the surface fermentation in France and Germany, than of those of England and Scotland.”—D. C. R.] Footnote 104: [28·4 c.c. = 1 fl. oz. approximately.] Footnote 105: [M. Pasteur has evidently employed the word “caseous” to express the curdy nature of the ferment he is describing, its plasticity and other peculiarities of physical character; but we are, nevertheless, tempted to suggest that he may have had in mind also the peculiar “cheesy” odour given off by these very yeasts, which he refers to in the text as containing a considerable intermixture of “caseous ferment.”—F. F.] Footnote 106: