EHRENBERG ON ORGANIC MOLECULES AND ATOMS. 573 
the above-mentioned process with colouring nutritive substances, and 
which possessed voluntary motions, but the entire and greatest dia- 
meter of whose body only amounted to the 7345 or gq of a Parisian 
line*. The smallest animal form, to which I have given the name of 
Monas Termo, is the same being as that which Otto Fr. Miller has 
delineated among the infusoria. I could perceive in the greatest indi- 
viduals of this animal form as many as six, and in the smallest as 
many as four, internal sacs coloured by blue indigo, which at times did 
not occupy quite half of the dimension of the animal. Such a sac 
therefore of the Monas Termo, if the animalcule measures 7345 
of a line, and if we suppose only four sacs occupying the half of it 
(therefore not one of the smallest), is ~3355 of a lin. in size, which is 
five times smaller than the minutest particles observed by Brown. At 
the upper part of this animal is perceived, as in all the monads, a 
powerful pushing aside of particles still smaller than themselves, when 
these come near to ‘them ; and it is therefore probable that they have 
a fringe of ten to twenty cilia near the anterior part of the mouth aper- 
ture, as in Monas Pulvisculus, and especially in the other still larger 
monads. Further, if even we suppose the single colouring particles 
with which the bellies are gradually filled not to be numerous, it would 
be against all probability not to think that they were filled by several 
particles. Let us however only suppose each sac to be filled by three 
colouring atoms,—which from the roundness made perceptible by the 
motion communicated to them we may well admit,—this alone affords 
a proof of the existence of material colouring particles of red and dark 
blue moving freely in water, which measure 34455 of a line, or gzghq5 
of an inch, in diameter ; and calculating these objects from the smallest 
of the animalcules, which by actual observation were found to be g555 
of a line in size, and which sometimes contained four coloured points 
in the hinder part of the body, these particles, which cannot be dis- 
tinguished individually by the eye with a magnifying power of 800, 
but yet aré to be recognised as corporeal, would amount to zg)p5 of a 
line, or 372555 Of an inch, which exceeds the molecules of Brown 
nearly twenty times in smallness. 
The above-mentioned transparent cilia about the mouth of these mo- 
‘nads (perceivable only by their action) may also approach in fineness 
those just cited; for if they were not less than 3515, of a line, or the 
multiple of forty-eight, with my magnifying power of 800, there would be 
no optical reason, except their transparency, why I should not see them 
with that power, as will be evident from the sequel of the memoir. I 
‘shall moreover direct attention to the fineness of other parts of these 
orgame living beings. The smaller monad-bellies are seen isolated in 
* J have already mentioned that I make use of a glass micrometer which 
measures +>39> Of an inch. 
