Fuly 7, 1870] 
NATURE 
185 
result of the burning of the zinc 100 units of energy as 
before. 
In like manner, if our electric battery is made to do 
work, thus forming a kind of engine, we shall have the heat 
produced by the current diminished by the exact equiva- 
lent of the mechanical effect which we have obtained from 
this engine. 
There is nothing for nothing in the universe of energy. 
B. STEWART 
ROUMEGUERE ON FUNGI 
Cryptogamie Illustrée, ou Histoire des Familles naturelles 
des Plantes Acotyledonées @ Europe. Famille des Cham- 
pignons. Par Casimir Roumeguére. (Paris: J. B. 
Baillitre. 1870.) 4to., pp. 164, figures 1700, 
HE numerous introductions to the study of fungi, 
whether as articles of food, objects of physiological 
and botanical interest, or as the cause or aggravator of 
disease both in the animal and vegetable world, which are 
constantly issuing from the press, or whose speedy ap- 
pearance is announced, are a certain proof of the daily 
increasing appreciation of the importance of a tribe which 
has often been considered as the mere offscourings of the 
earth, and worthy only of the title of “abominations.” 
These publications of course are of very different value, 
and the glowing terms in which they are announced some- 
times lead only to disappointment after an inconvenient 
outlay. Asa striking instance, Valenti-Serini’s work on 
doubtful or poisonous fungi of the neighbourhood of Turin 
may be mentioned, which was characterised in the “ An- 
nals of Natural History” as “this important work,” its 
true characters being admirably exposed by Mr. Worth- 
ington Smith in “Seemann’s Journal of Botany ;” and un- 
- sparing as the remarks are, I consider that they are com- 
pletely justified. It is simply a disgrace to the Academy 
under whose auspices it is published.* 
This is not, however, the case with the publication 
whose title is given above ; for though it is far from being 
free from faults, and the illustrations, though selected 
with considerable skill, are in some cases so coarse as 
almost to render them useless ; still there is such a mass 
of information as may make it acceptable even to those 
who are well versed in the subject ; and though unfortu- 
nately the several matters which come under review are 
seldom thoroughly worked out, yet they indicate the 
proper line of research and the best sources of informa- 
tion, in such a manner as to ensure it a hearty welcome. 
Every possible nook and corner of the mycological library 
seems to have been thoroughly ransacked, and that 
without any national prepossession such as occasionally 
detracts from the credit even of highly approved authori- 
ties. Indeed I was not a little surprised to find how 
diligently English works on the subject had been sifted, 
and not the less to recognise an allusion even to a sec- 
tional address at Norwich, though the remarks of its 
author have not been quite correctly interpreted. 
It is not likely that there should be much novelty in so 
unpretentious a work, and perhaps it may be as well that 
no new views should be propounded, founded on imperfect 
data. It is a great matter to find no glaring errors likely 
* T need only refer to Tab. 30 to justify this remark ; and this instance is 
not a solitary one. 
to mislead ; though here and there the drift of what has 
been written may have been misunderstood. 
It is scarcely possible to overrate the importance of the 
study of fungi in any of the points of view which were 
enumerated. The Society of Arts and the Horticultural 
Society of London have very properly called attention to 
the great importance of fungi as articles of food, by en- 
couraging inquiry or offering rewards for the best collec- 
tions of esculent, doubtful, and poisonous species. The 
South Kensington Museum has also done its part. The 
very faithful set of drawings by Mr. W. G. Smith, ex- 
hibited on its walls, and the admirably prepared speci- 
mens by Mr. English—which retain their form perfectly, 
and, to a great extent, their proper colours—must even- 
tually facilitate the due discrimination, which, as in the 
case of other vegetable esculents, must be matter of 
experience. It is quite lamentable to reflect what a vast 
quantity of wholesome food, and food which, from its 
chemical composition, may profitably replace the con- 
sumption of meat in the labourer’s family, is utterly 
neglected, either from ignorance or prejudice. 
In the second point of view as regards their physio- 
logical and botanical interest, it need only be mentioned 
with respect to the former, that, with the exception of 
the true algae, the phenomena of impregnation cannot be 
studied more profitably than in those wonderful plants 
which occur on dead animals or decaying vegetables in 
water, and which are, undoubtedly, aquatic forms of 
various moulds, though in some respects they approach 
the alge. Then as. respects a biological point of view, 
the question of the origin of atmospheric germs, one of 
the most difficult of solution which can engage the atten- 
tion of the microscopist, and which, in my opinion, has 
never been carried out so as to trace accurately, and free 
from all doubt, the development of the minute bodies 
which occur in fluids, whether of organic or inorganic 
composition, into higher forms; while the botanist will 
find a variety of form and structure which is scarcely 
surpassed in the higher branches of the science. 
As regards the third point. If we consider fungi as 
the causes or aggravators of disease, it may be remarked, 
that, notwithstanding all that has been written on the 
subject, a great deal still remains to be discovered. The 
dreadful forms of Erysipelas and Hospital Gangrene, 
which occur so fatally in London hospitals, are, in all 
probability, dependent somehow on fungi, though the 
matter has not, hitherto, been found capable of proof, and 
whatever may be thought of Dr. Tyndall’s views, the 
medical world cannot be too thankful to him for bringing 
the matter so prominently before the public.* The same 
also may be said with respect to Dr. Hallier’s specula- 
tions, though, as I believe, they have been justly challenged 
both here and on the Continent. 
A great deal is known about the influence of fungi in 
the production of disease in plants, but much more re- 
mains to be discovered. It may, eventually, prove that 
* That the reproductive bodies of the larger fungi and moulds are widely 
carried about by the air, will be very evident to any one who has seen the 
clouds of spores which, in some cases, arise like smoke on the least agitation, 
Some years ago two flakes of snow were sent to me from Hampstead, pre- 
pared as microscopic objects, with the intention of exhibiting the organic 
matters which they might carry down with them in their course, and both, 
undoubtedly, contained perfect spores of fungi. Much more then may we 
expect that organisms which do not exceed a thirtieth or a fiftieth part of 
their diameter, and which are quite invisible except under very high magni- 
fying powers, should be present everywhere to perform their functions as 
putrefactive ferments, 
