1862. ] DR. T. S. COBBOLD ON HUMAN ENTOZOA. 293 
Schistosoma in favour of Bilharzia, which he admits has the priority. 
Though it is of little consequence which name be retained, the genus 
itself is one of remarkable interest, not merely in a structural point 
of view, but also from its prevalence on the borders of the Nile. 
The first specimens were discovered by Dr. Bilharz, of Cairo, in the 
portal system of blood-vessels; and others were subsequently ob- 
served by him, Griesenger, Reinhard, and Lautner in the veins of 
the mesentery, bladder, and other parts, giving rise to a formidable 
and very prevalent disease. The anatomy of Bilharzia has been 
fully described by the original discoverer and by Kiichenmeister ; 
but I would observe, in passing, that it is rather singular that Moquin- 
Tandon should express his belief that the sexes have been mistaken 
by such competent authorities. The circumstance of the smaller 
form being carefully described by them as furnished with uterine 
ducts containing eggs ought to leave no doubt in our minds as to the 
correctness of the generally received opinion, unless we have distinct 
evidence to the contrary. In connexion with this subject I would 
also again call attention to the circumstance of my having discovered 
the second species of Bilharzia (B. magna) in the portal system of an 
African Monkey (Cercopithecus fuliginosus). Those who pay regard 
to the distribution or limitation of particular forms will see in this 
fact a curious illustration of the affinities of habit ; for there can be 
little doubt that the Sooty Monkey procures the larvze of its Bil- 
harzia from a source similar to that from which our Egyptian bre- 
thren procure the larvee of B. hematobia, and it is not a little sig- 
nificant that the genus in question should only at present be known 
to infest men and monkeys. For further particulars in regard to 
this parasite I must refer to my previous papers in the ‘ Linnean 
Transactions’ (vol. xxii. p. 364), ‘ Linnean Proceedings’ (vol. vy. 
Zool. Div. p. 30), ‘ Zoological Society Proceedings’ (1861, p. 118), 
and in the ‘ Intellectual Observer’ (vol. i. p. 352). 
7. TETRASTOMA RENALE, Delle Chiaje. 
T. renale, Delle Chiaje, Diesing, Dubini, Leidy, Weinland. 
The occurrence of this entozoon as a human parasite appears 
hitherto to have escaped the notice of English zoologists, although 
discovered by Lucarelli and Delle Chiaje in 1833. All that we now 
know of it is due to the original description of Chiaje, from whose 
‘Elmintografia Umana’ we learn that it attains a length of 5 lines, 
has an oval flattened body, and is furnished with four suckers disposed 
in a quadrate manner at the caudal extremity. The reproductive 
orifices are situated near the mouth. It infests the tubes of the 
kidney. 
8. HEXATHYRIDIUM PINGUICOLA, Treutler. 
H. pinguicola, Treutler, Jordens, Brera, Leidy, Weinland. 
Hexastoma pinguicola, Cuvier. 
Linguatula pinguicola, Lamarck. 
Polystoma pinguicola, Zeder, Rudolphi, Bremser, Delle Chiaje, 
Owen, Dujardin, Dubini. 
