C. Dobell 
1 VQ 
I .).) 
They were probably coccidia of some sort, though even this is open to question. 
Even their habitat cannot be exactly determined—in fact we know only that 
they occurred in some part of the gut (“Darmkanal"), and not in the liver. 
Leuckart! s cases. In his books on the animal parasites of man, Leuckart 
cites several cases of coccidiosis. These have long been copied from book to 
book, together with Leuckart’s opinions on them, without criticism. As they 
have thus come to occupy an important place in the literature of this subject. 
I shall examine them in some detail. 
It should be noted first that none of the cases cited by Leuckart was his 
own. Thev were all discovered and communicated to him by others. As noted 
above, he makes reference in the first edition of his book (Leuckart, 1863) to 
the “psorosperms” previously found in the human liver by Gubler. In the 
Appendix to this work (p. 740) he was able to add a second, and apparentlv 
similar case, communicated to him bv a Dr Dressier of Prague. The case is 
mentioned by him again later (Leuckart, 1879, p. 281), and accompanied on 
both occasions by a woodcut from the sketches which Dressier had made of 
his findings. So far as I can determine, Leuckart himself never saw the actual 
specimens: he saw only the drawings which he reproduces. From the descrip¬ 
tion and figures the following facts can be obtained. Dressier found three 
small nodules—varying in size from that of a millet seed to that of a pea—in 
the margin of the liver of a human cadaver. Nothing further is recorded about 
the case itself. Inside the nodules was a whitish pulp, containing oval bodies 
which were—to judge from the drawings—the unsegmented oocysts of a 
coccidian. Their length appears to have been about 18-20/x; otherwise thev 
are not unlike the oocysts of Eimeria stiedae from the fresh liver of a rabbit. 
If we accept the statement that they were “psorosperms” or “ coccidia,” there 
is, nevertheless, no information in the descriptions which will enable us to 
determine the genus, let alone the species, to which they actually belonged. 
The second case cited by Leuckart (1879, p. 281) was discovered by one 
Prof. Sattler of Vienna. A preparation, which he had made for the purposes 
of a course in pathological anatomy, was found to contain “a dilated bile-duct 
with greatly proliferated epithelium and coccidia ” (Leuckart). Nothing 
appears to be known about the case from which the material was obtained. 
It is implied, though not definitely stated, that it was human. Sattler did not 
send the preparation to Leuckart, but to a Prof. Peris of Giessen, who sent it 
on to him, together with a drawing which is not reproduced. Leuckart savs 
he was able to convince himself “of the true nature” of the coccidia bv his 
examination of the specimen: but he notes that “the contents of the coccidia" 
had been “completely cleared” by mounting in glycerine, so that “the bodies 
in question could easily have been taken for distomum eggs (D. lanceolahnn 1 )” 
1 It is perhaps worth noting here that the eggs of this trematode (now known as Dicrocoelium 
lanccatum ) are 38 n to 45 /j. in length or rather more than twice the length—that is, if his own 
figures are correct—of the “coccidia” which Leuckart says could be mistaken for them. 
