132 LEEUWENHOEK AND HIS “ LITTLE ANIMALS ”’ 
whole year in vinegar, it yet retaineth its pungency); I 
did now’ place anew about 3 ounce of whole pepper in 
water,’ and set it in my closet, with no other design than 
to soften the pepper, that I could the better study it. 
This pepper having lain about three weeks in the water, 
and on two several occasions snow-water having been 
added thereto, because the water had evaporated away ; 
by chance observing this water on the 24th April, 1676, 
I saw therein, with great wonder, incredibly many very 
little animalcules, of divers sorts; and among others, 
some that were 3 or 4 times as long as broad, though 
their whole thickness was not, in my judgement, much 
thicker than one of the hairs wherewith the body of a 
louse is beset.2 These creatures were provided with 
exceeding short thin legs in front of the head (although 
I can make out no head, I call this the head for the 
reason that it always went in front during motion). 
This supposed head looked as if ’twas cut off aslant, in 
such fashion as if a line were drawn athwart through 
two parallel lines, so as to make two angles, the one of 
110 degrees, the other of 70 degrees. Close against the 
hinder end of the body lay a bright pellet, and behind 
this I judged the hindmost part of all was slightly cleft. 
These animalcules are very odd in their motions, oft-times 
tumbling all around sideways; and when I let the water 
run off them, they turned themselves as round as a top, 
and at the beginning of this motion changed their body 
into an oval, and then, when the round motion ceased, 
back again into their former length.’ 
cis Bi ate Fie i 5 
! The exact date is not recorded ; but it will be seen from the next sentence 
that the pepper was laid in water during the first few days of April, 1676. 
® Unfortunately L. omits to state what kind of water he used. Had he 
done so, it would have afforded some help in attempting to determine the 
organisms which he found in it later. 
* About 3. See p. 337 infra. 
‘From the foregoing description I think it highly probable that the 
animal observed was Bodo caudatus (Duj.) Stein,—one of the commonest 
protozoa found in organic infusions. The description, as far as it goes, fits 
this animal almost exactly. 
