PARASITES OF MAN. 7 
Pah Sl Dy sin OF MAaNGt 
BY T. SPENCER COBBOLD, M.D., F.R.S., ETC. 
(Continued from Vol. I., page 328.) 
Five more human nematodes remain to be noticed. Of these, two 
are excessively common in man, anda third, though rare asa human 
parasite, is very abundant in carnivorous animals. The three entozoa 
thus particularised are popularly known as the threadworm, the 
lumbricus, and the cat’s worm. In the present communication I shall 
deal only with the first of these three common species, adding a brief 
notice of the Cochin China anguillules. The threadworm is just one of 
those species about which one does not like to say very much in public ; 
and even that which is whispered about these entozoa in consulting rooms 
has to be conveyed to the victim’s ears with tact and delicacy. As I 
have no professional motives in declaring my meaning I will mention an 
illustrative case, leaving it to the judgment of the Society whether the 
facts be published or not. An unmarried gentleman, the happiness of 
whose immediate future was intimately bound up with his speedy 
restoration to health, freely communicated to me the painful nature of 
his sufferings due to the presence of these little parasites. Thesymptoms 
cannot be stated in detail. Let it suffice me to say that the obnoxious 
guests had invaded the host by myriads, bringing their victim down to 
anemaciated und otherwise pitiable condition. Knowing the essential 
conditions of infection, I ventured to hint that the victim must in 
some way or other have swallowed one or more entire female parasites of 
this species (Oxyuris vermicularis). The suggestion was a hard though 
' happy hit; for it speedily brought the confession that in times of great 
distress the victim had, en revanche, seized hold of the living parasites 
and crushed them between his teeth. As, without doubt, most, if not 
all of the entozoa thus bitten in halves, were female worms, and as, 
moreover, each female parasite encloses myriads of eggs—whose contained 
embryos do not require a change of hosts—it is certain that thousands, 
not to say tens of thousands, of living germs were thus directly 
conveyed to the human territory. In this way the victim, originally 
seeking to revenge himself on the sexually mature parasites, could only 
have produced momentary pangs in the worms themselves, but for 
himself, he had thus unwittingly prepared that far more terrible and 
prolonged revenge which was afterwards exercised, unconsciously, by the 
progenies of the parent worms he had thus mutilated. 
NEMATODA CONTINUED. 
37.—Oxyuris vermicularis, Bremser. 
Synonymy.—Ascaris vermicularis, Linneus. 
Larve.—Only generally known in the embryonic state. Whilst 
within the egg they are at first tadpole-shaped, but under 
suitable conditions of heat and moisture they rapidly assume a 
vermiform character. 
* Read to the Microscopical Section of the Birmingham Natural eo and 
Microscopical Society, December 17th, 1878. On Dr. Cobbold’s behalf M vets 
Hughes, F.L.S., exhibited specimens both of human and equine preriee 
(Oxyuris vermicularis and O. cur vula). The latter species is better known as the 
hacia of the horse; female examples sometimes attaining a length of nearly five 
inches. 
