‘é 
220 LEEUWENHOEK AND HIS “‘ LITTLE ANIMALS ”’ 
particles made up of globules joined together; though 
the thin matter’ of one was much thicker and stickier 
than that of the other, and there were some little clouds 
floating through it. 
I have furthermore examined the biles of fowls, 
turkeys, ete., and in them I also found very little 
globules floating, and irregular particles composed of 
globules stuck together. 
I think there can be no doubt that the “ oval corpuscles ’”— 
called eyronde deeltgens in the original—which Leeuwenhoek 
discovered in the gall-bladder of one of his “ three old rabbits,” 
were the oocysts of the coccidian Himeria stiedae; while the 
comparable structures which he found in the bile of sheep and 
oxen were, equally certainly, the eges of trematodes.” But as 
I have already discussed this subject in some detail elsewhere,’ 
I shall say no more about it here. If my interpretations be 
correct, then the foregoing extract records the first observations 
ever made upon the Sporozoa or upon any parasitic protozoon. 
It is true that Leeuwenhoek himself did not realize that he 
had discovered a stage in the life-history of a brand-new kind 
of parasite: but the same can be said also of others who are 
now generally credited with the discovery of the Coccidia.'* 
The fact remains, none the less, that he saw and described— 
though his description was not published for nearly 250 years— 
a coccidial parasite long before all other men. 
* i.e., the liquid part of the bile. 
* Fasciola hepatica—the worm itself—was well known to L.; for the 
Dutch anatomist Bidloo (1649-1713) dedicated a little memoir to him, in 
1698, in which it was described and figured. At a later date, L. himself 
wrote a letter to the Royal Society on the ‘ Worms observ’d in ae 
Livers ’’—of which an English abstract was published i in Phil. Trans. (1704), 
Vol. XXIV, p. 1522. The original letter is extant, and is dated 3 Nov. 
1703. It was not included in the Dutch or Latin collected works. 
* See Dobell (1922). 
“ The lesions of hepatic coccidiosis in the rabbit appear to have been 
first depicted by [Sir] Robert Carswell (1793-1857 ; Professor of Pathological 
Anatomy at University College, London) in the year 1838. He regarded 
them as “the seat of tuberculous matter.” The oocysts of E. stiedae were 
first figured and described in print by Dr Thomas Gordon Hake (1809- 
