224 LEEUWENHOEK AND HIS ‘“‘ LITTLE ANIMALS” 
of them was made up of 6 separate globules :' and further, 
there lay, among all this material, globules whereof 6 of 
‘em together would make up the bigness” of a blood- 
corpuscle. These last were in such great® plenty, that 
they seemed to form a good third of the whole’ material: 
while there were besides many globules which were so 
small, that six-and-thirty of ’em would make up the bigness 
of a blood-globule.’ 
All the particles aforesaid lay in a clear transparent 
medium, wherein I have sometimes also seen animalcules ° 
a-moving very prettily; some of ‘em a bit bigger, others 
a bit less, than a blood-globule, but all of one and the 
same make. ‘Their bodies were somewhat longer than 
broad, and their belly, which was flatlike, furnisht with 
sundry little paws, wherewith they made such astir in the 
clear medium and among the globules, that you might e’en 
fancy you saw a pissabed‘ running up against a wall; and 
albeit they made a quick motion with their paws, yet for 
all that they made but slow progress. Of these animalcules 
I saw at one time only one in a particle of matter as big 
as a sand-grain; and anon, at other times, some 4, 5, or 
even 6 or 8. I have also once seen animalcules of the 
same bigness, but of a different figure. * 
* At one time L. held the curious belief that each red blood-corpuscle 
was composed of 6 aggregated smaller “globules”. This was an error 
probably due, I think, to misinterpretation of diffraction-images. 
* i.e., in volume—not in diameter. 
* groote stands here in the MS. but not in the printed letter. 
* gantsche MS. omitted from printed letter. 
° 7.e., their diameter was between + and + of that of a human red 
blood-corpuscle. 
* The following description—as I have elsewhere tried to show (Dobell, 
1920)—is a graphic account of the flagellate Giardia (=Lamblia) 
intestinalis. 
" The woodlouse or sow-bug (Oniscus asellus). The Latin translation of 
this passage has given rise to many curious misunderstandings. Cf. Dobell 
(1920), where “ pissabeds”’ are more fully discussed. 
* As no other details are given, it is impossible to identify these 
organisms. Possibly they were Trichomonas or Chilomastiz. 
