1862.] DR. T. S. COBBOLD ON HUMAN ENTOZOA. 301 
pond, whosé muddy sediment swermed with the microscopic Tank- 
worm (Urolabes palustris, Carter), twenty-one were attacked with 
Dracunculus during the year ; whilst the boys of other schools bath- 
ing elsewhere in the island were not infected, with the exception of 
one or two individual instances here and there. This remarkable 
occurrence, taken in connexion with Schneider’s discoveries (respect- 
ing the causes inducing sexual maturity in Alloionema appendiculatum 
infesting the Black Slug, and in Pelodytes hermaphroditus in- 
festing Snails), and also in combination with a multitude of other 
facts, some recorded by recent investigators, and others handed down 
to us by earlier writers, convincingly suggest the following conclu- 
sions :—(1.) The Dracunculus is a bisexual nematode, the female 
being parasitic during a portion of its lifetime. (2.) The male is 
probably very much smaller, non-parasitic so far as animals are con- 
cerned, and in all likelihood a constant inhabitant of fresh water and 
the mud of marshes or low-lying districts in the East. (3.) Guinea- 
worms do not gain access to the human body indirectly, by the 
mouth or stomach of the host, but directly, by penetrating the skin. 
(The young when introduced into the stomach of animals rapidly 
perish, as proved by Dr. Forbes.) (4.) The young acquire sexual 
maturity after their escape from the parent, the sexes associating in 
muddy waters during the monsoon, soon after which period the 1nales 
probably perish, the females being left to watch their opportunity 
for further development by migration into the human body. (35.) 
Within the host it gives rise to a formidable entozootic disease (dra: 
contiasis of Galen), which, after prolonged monsoons, is not unfre- 
quently severely endemic. (In the above remarks I have referred 
more particularly to the writings of Busk in ‘ Trans. Micr. Soc.,’ old 
series, vol. ii. p. 65 ; of Moquin-Tandon in his ‘ Zoologie Médicale ;’ 
of Robin in ‘ Gazette Médicale de Paris,’ 3rd series, vol. x. p. 365; 
and of Carter in ‘ Annals of Nat. Hist.’ 3rd series, vol. iv. &c.) 
15. Firarra Lentis, Diesing. 
F. lentis, Diesing, Moquin-Tandon, Weinland. 
F. oculi-humani, Nordmann, Gescheidt, Ammon, Siebold, Leidy. 
F. oculi, Owen, Moquin-Tandon. 
As Kiichenmeister suggests, this worm may possibly turn out to 
be identical with the Filaria lacrymalis (Gurlt), a viviparous species 
infesting the eye of the horse. It was first discovered by Nordmann 
(1831) in a case of lenticular cataract under the care of Von Grafe, 
and subsequently found by Jiingken under similar circumstances. 
Under the title of F. oculi, Moquin-Tandon (in his ‘ Zoologie Mé- 
dicale’) speaks of certain minute Filarie, “not uncommon in the 
negroes of the Angola coast ;”’ and he gives other localities of its 
occurrence. As, however, he does not state what part of the body 
is infested by them, I am inclined to think the authorities he quotes 
have mistaken the little Oxyurus vermicularis for the species in 
question. In both the well-known cases above referred to, the 
Filarie appear to have been immature, notwithstanding that the 
first was described as possessing ovaries, oviducts, &c. 
