684 
POPULAE SCIENCE EEVIEW. 
its delivery through the kidneys. The researches of Moqiiin-Tandon, Lister, 
Rossmassler, Gegenbaur, Drapariiand, and others, on this subject are discussed 
and referred to. 
The Origin of the Vinegar-Eel {Bhahditis aceti). — The researches of 
M. Davaine upon the subject of the vinegar-worm reported to the French 
Academy on the 8th of August, have given another blow to the sponta- 
neous generation theory. The vinegar-worm, or eel, as it is more fre- 
quentl}’’ styled, is a species of annulose animal, of very low t}q)e, found in 
vinegar which has been prepared from fruit. The circumstance that its 
habitat is such a peculiarly artificial one has led the advocates of heterogeny 
to advance this creature as an argument in favour of their views, it being 
contended by them that, as it only lives in an artificial compound, it must 
be the result of spontaneous generation. M. Davaine’s inquiries, the ’conclu- 
sions resulting from which have just been laid before the “ Academy,” give 
us many new ideas concerning the habits and origin of the vinegar-eel. His 
researches show that acidity alone is not a condition under which the worm 
can exist. The mineral acids, and also the organic ones — oxalic and citric — 
when diluted to the strength of the vinegar in which the creature lives, 
destroy its life in the course of a few hours ; whilst, on the contrary, a solu- 
tion of sugar is so favourable to its vitality that it causes it to propagate 
very rapidly. Although the vinegar-eel dies after about eight days when 
kept in pure water, it lives for several weeks in this liquid if it contains 
from one to the two thousandth part of sugar. In water containing five per 
cent, of sugar it multiplies with great rapidity. There seems to be a relation 
between the degree of propagation and the per centage of sugar : thus, gene- 
ration increases notably up to about 30 per cent., it remains stationary at 
40 per cent., and ceases altogether — the worms dying — at 50 per cent. The 
worm multiplies to a greater extent in sugar-water in which the acid is 
constantly neutralized, than in the acid solution. From these discoveries, 
M. Davaine was led to place some vinegar-eels in neutral or slightly acid 
fruits, such as peaches, prunes, apricots, raisins, gooseberries, apples, pears, 
melons, &c., and in all these they propagated at a prodigious rate. In vege- 
tables, such as peas, beet-root, carrots, &c., they also thrived. Under the 
various conditions of life to which they were subjected, the worms underwent 
no modification. These facts indicate very clearly what is the true habitat 
of the vinegar-eel. It lives and propagates itself by myriads in those fruits 
which faU upon the ground, and those sweet succulent branches which lie 
upon the soil. It is endowed with considerable powers of locomotion to 
enable it to go in search of food ; and, as M. Davaine has experimentally 
proved, it can live for several weeks in moist soil which contains no food 
whatever. It may therefore be regarded as established that the vinegar-eel, 
so far from being developed spontaneously during acetic fermentation, is 
introduced into the liquid vinegar in the grapes, apples, and pears, which are 
used in its manufacture, and which have lain for some time upon the ground ; 
and that it is perpetuated in the vessels used for the fermenting process, and 
which are employed for an almost unlimited period for the purpose of preparing 
vinegar. 
A new silkworm is reported to have been cultivated in America. In the 
Canadian Naturalist (Vol. ii. No. 3) we find it stated that, after numerous 
