of
fungi. He could never trace the process without observing at the very
first evolution of carbonic acid, the formation of yeast-cells,
although it is very difficult to decide certainly which precedes the
other.' His own opinion is in favour of the commencement by the
yeast-cells.

Another noteworthy subject, is Dr W.J. Burnett's paper to the American
Association, 'On the Relation of the Distribution of Lice to the
Different Faunas,' in which he endeavours to demonstrate, that the
creation of animals was a multiplied operation, carried on in several
localities, and that they do not derive from one original parent
stock. Different animals have different parasites; but, as he shews,
the same species of animal has the same parasite, wherever it may be
found. According to Latreille, the _pediculus_ found in the woolly
heads of African negroes 'is sufficiently distinct from that of the
Circassian to entitle it to the rank of a distinct species;' from
which, and similar instances, the doctor concludes: 'Whatever may be
urged in behalf of the hypothesis of the unity of the animal creation,
based upon the alleged metamorphosic changes of types, it is my
opinion that the relations of their parasites, and especially the lice
which are distributed over nearly all of them, must be considered as
fair and full an argument as can be advanced against such hypothesis,
for it is taking up the very premises of the hypothesis in
opposition.' Dr Burnett will perhaps find Sir Charles Lyell ready to
break a lance with him on the point at issue.

Something interesting to workers in metal has been brought before the
Franklin Institute at Philadelphia--it is a method of giving to iron
the appearance of copper, contrived by Mr Pomeroy of Cincinnati, who
thus describes it--rather laboriously, by the way:--

'Immerse the iron in dilute sulphuric acid, for the purpose of
cleansing the surface of the article which is to be coated; and thus
cleansed, submit the iron to a brisk heat to dry it; when dry, immerse
the article in a mixture of clay and water, and again dry it so as to
leave a thin coating of the clay on its surface: it is then to be
immersed in a bath of melted copper, and the length of time requisite
for the iron and copper to form a union, will depend on the thickness
of the article under operation. The object of the clay is to protect
the copper from oxidation during the process of alloying or coating,
and to reduce it to the requi