56 
POPULAR SCIENCE RE HEW. 
be found that the laws, not only of molecular but of alternate 
generation and parthenogenesis, prevail among them, and one 
frequently passes into another. Their production is largely 
dependent on temperature, state of the atmosphere, light — 
especially the sun’s rays — and other physical conditions. 
At other times, it happens that the molecular mass, instead 
of being transformed into animalcules, gives origin to minute 
fungi. In this case the molecules form small masses, which 
soon melt together to constitute a globular body, from which a 
process juts out on one side. These are Torulo3, which give 
off buds which are soon transformed into jointed tubes of 
various diameters, terminating in rows of sporules {Fenicil- 
limn), or capsules containing numerous globular seeds (Aspei^- 
(jillus). Occasionally filaments are formed from the direct 
melting together of molecules arranged longways {Leptoikvix), 
(See fig. 1, e.) 
Here also I think various forms regarded as distinct plants 
pass into one another — especially torulse, which are only em- 
bryonic forms of higher fungi. In all these cases no kind of 
animalcule or fungus is ever seen to originate from pre-existing 
cells or larger bodies, but always from molecules. 
That we should sometimes have animalcules, and at others 
fungi, is a well-known fact, the exact causes or conditions pro- 
ducing which are not yet explained. The Panspermatists, of 
course, are of opinion that the germs in the atmosphere are of 
many kinds, and that as they fall into various infusions they 
produce different results, in the same manner that varieties in 
ova or seeds develop themselves in peculiar localities or special 
soils. This assumption, however, seems to me opposed by the 
following experiment: — 
If an infusion be placed in a deep glass vessel, which again 
stands in the centre of a shallow vessel containing the same 
infusion, and the whole covered with a large bell glass, it will 
1)0 found in eight da 3 ^s that on the surface of the former are 
numerous ciliated animalcules, while on that of the latter only 
bacteria and vibrios exist. The experiment may be reversed, 
for if the shallow vessel be filled to the brim, and the deep 
vessel has only its bottom covered, then the ciliated microzoa 
will appear in the former, and the non-ciliated in the latter.* 
It is difficult to explain how germs falling from the air on the 
same infusion, under identically similar conditions, with the 
exception that the fiuid is in vessels of different forms, can vary 
the results. Whereas the fact that the higher infusoria are 
formed secondarily out of the disintegrated mass of the simpler 
• Pouchet’s ‘^Xouvclles Expdneuces,” &c.,‘ pp. 135, 243-245. Paris, 
