148 
LEEUWENHOEK AND HIS ‘“‘ LITTLE ANIMALS ”’ 
cules and roundish animalcules, I discovered three which 
had the figure of a pear, only with this difference, that on 
the underside of their body they were flat.’ Such a sort I 
had not seen till now in any water. And I had such a 
hunt for these creatures, because they were so few, that I 
gave no heed to the very smallest ones. 
The 9th ditto, I perceived but one of the animalcules 
that had the figure of a pear, in four several observations. 
And though there was still quite a lot of water with the 
pepper, yet I added more well-water to it, because the 
pepper-water was become rather thick. Ditto, in the 
afternoon, about 4 o’clock, I could see none at all of 
the animalcules that had been in great plenty in the 
well-water ere I poured it on the pepper; neither could 
I discover any of the animalcules that had the figure 
of a pear. 
The 10th ditto, in the morning, the roundish and the 
long animalcules were now in such inexpressibly great 
crowds, that they far exceeded in number all the animal- 
cules that I had ever seen up to this date in any waters. 
Moreover, I could discern no other sort. 
On the 14th ditto, I could remark no change since the 
10th, save only that 1 now saw again animalcules which 
had the figure of a pear; and I saw there besides an 
animalcule with a tail.’ 
The 15th ditto, | saw more animalcules that had the 
figure of a pear, and two or three animalcules with tails. 
And I perceived at this time that the pear-shaped 
animalcules kept not against the surface of the water, 
like the other creatures, but that they swam a bit deeper 
under water. Their thickness was about that of a single 
small thread of a silk-worm,’ and they were about 13 times 
’ Evidently a hypotrichous ciliate. 
? t.e., Vorticella. 
° Cf. Letter 146. 20 April 1702. To the Landgrave of Hesse. Printed 
fully in Dutch and Latin collective editions. 
