290 DR. T. S. COBBOLD ON HUMAN ENTOZOA.  [Nov. 25, 
rejected by Blanchard, is now generally accepted as correct. In 
other particulars, concerning the mode of distribution of the aqui- 
ferous vessels, the representations of the French naturalist appear to 
be trustworthy, and my own injections confirm his statements in all 
essential points*. Up to the present hour a complete history of the 
development of this species has not been made out; but the recent 
investigations of Van Beneden, Pagenstecher, Wagener, Filippi, and 
others enable us to form tolerably accurate conclusions respecting 
the abode and migrations of its larvee. As, however, I have recently 
published the results of my investigations on this point in my paper 
“On the Common Liver Entozoon of Cattle,” in the pages of the 
© Intellectual Observer’ (vol. i. p. 115 e¢ seq.), I need not now reca- 
pitulate the deductions there recorded ; but I may observe, in passing, 
that a well-sustained series of researches are still wanting to com- 
plete the chain of evidencet+. The costly nature of these investiga- 
tions has alone prevented my further prosecution of the necessary 
experiments. Hitherto, only nine instances have been recorded of 
the occurrence of this parasite within the human body ; and for par- 
ticulars respecting these I may also be permitted to refer to my 
«« Synopsis of the Distomide,” in the fifth volume of the Journal of 
the Proceedings of the Linnean Society. 
2. DisromA crassum, Busk. 
D. crassum, Cobbold, Simonds. 
D. buskii, Lankester, Moquin-Tandon. 
Dicrocelium buskii, Weinland. 
This is a good species, and appropriately named ; for, although 
Von Siebold (in Miiller’s Archiv for 1836, p. 234, and in his Lehr- 
buch, vol. i. p. 143) refers to a Distome infesting Hirundo urbica 
under this title, he has given no description of the worm. Diesing 
places Von Siebold’s D. crassum among his species inquirende, and 
it is very probably identical with the D. maculosum of Rudolphi. 
No other instance has occurred since the original fourteen specimens 
were discovered by Mr. Busk in the duodenum of a Lascar. From 
a careful examination of three examples, severally presented hy the 
discoverer to the Museum of the Royal College of Surgeons, the 
Museum of the Middlesex Hospital Medical College, and to my pri- 
vate collection, I am satisfied that it is generically distinct from the 
above; but it is unnecessary to insist further on this distinction, as 
* Specimens of the Fasciola gigantea, thus prepared, were exhibited by me at 
the Glasgow Meeting of the British Association in 1855, a description of them 
being given in the ‘ Report,’ Sect., p. 108; and a more extended account of the 
same appeared in ‘ Edin. New Phil. Journ.’ for 1855, plate 7. 
+ Since the above was written, I have received a communication from Professor 
Leuckart, of Giessen, in which he mentions that he has at last succeeded in solving 
many points respecting the phases of development through which this species 
passes. A full account of these changes will doubtless appear in the second di- 
vision of his valuable work (Die menschlichen Parasiten) now in course of pub- 
lication. 
t Ihave forwarded this specimen to Prof. Leuckart in exchange for other rare 
parasites.—T. S. C., Jan. 10, 1863. 
