NEMATODA, THREAD-WORMS 551 



used in common, or by various utensils which may be contaminated with ova. 

 Ova have been repeatedly found in the dirt of the finger nails of oxyuris hosts. 

 This observation sufBciently explains why oxyuris hosts are rarely found iso- 

 lated in families, pensions, etc., and the same finding also explains the well- 

 known tenacity of the affection, which has been known to physicians for a 

 long time. The oxyuris host evidently infects himself anew almost daily, or 

 even every night. 



The embryos which have been set free in the stomach develop to sexual 

 maturity in the small intestine. The impregnated females enter the cecum, 

 and there await the time for depositing their ova. When this period has 

 arrived, they wander toward the rectum, or beyond this, and are discharged. 



No age is exempt from the parasite, but it is particularly frequent in 

 children. Great uncleanliness, huddling together, and sleeping with infected 

 persons favor contagion. The expulsion of parasites is so constant because of 

 their rapid increase that opportunity for the entrance of new ova may be long 

 delayed, and it is, therefore, not rare for persons to harbor a parasite for a 

 great many years. 



If the number of parasites is small, they betray their presence only now 

 and then by itching and burning in the rectum. In sensitive individuals, after 

 passing through the anus, a few parasites only may cause a number of symp- 

 toms. These disturbances are decidedly increased by the presence of consid- 

 erable numbers of the oxyuris. By their serpentine movements in the lower 

 portion of the intestine they produce intense itching in the anus. This is par- 

 ticularly marked as soon as the patients go to bed. Sleep is prevented or is 

 interrupted. The periodicity of these symptoms is conspicuous, and as yet 

 no sufficient cause for this has been assigned. Large numbers of oxyuris cause 

 marked catarrhal irritation of the intestinal mucous membrane, perhaps also 

 erosions, which are brought about by the active boring movements of the head 

 extremity of the animals. The venous vessels dilate as in the case of hemor- 

 rhoids. Frequently oxyuriasis is complicated with hemorrhoidal conditions 

 and chronic catarrh of the rectum. In consequence of this the bowels not 

 rarely become irregular and diarrheic, and the symptoms of tenesmus appear. 

 A number of consensual symptoms may also develop, which in children readily 

 lead to onanism. Oxyuris may cause pruritus ; in the vagina in girls a leukor- 

 rhea, in the prepuce in boys a balanitis. Marro found in a pus cyst well-pre- 

 served ova of oxyuris vermicularis. 



Eeflex symptoms of the most varied kinds, due to oxyuris, are said to occur 

 with particular frequency in neuropathically predisposed individuals; I have 

 gathered a number of observations of this kind. At all events, the presence 

 of numerous parasites is not without an influence on the affected organism. 

 In feeble persons, particularly in children, we note that the nutrition suffers, 

 the patient becomes weak and anemic, and there is loss of weight. After 

 expulsion of the parasite, however, the entire condition of the carrier often 

 improves suddenly. Occasionally the oxyuris wanders into the stomach, from 

 here to the esophagus, to the mouth or to the nose. Hartmann saw the fre- 

 quent expulsion of oxyuris from the nose. It was accompanied by the most 

 severe irritative symptoms, epileptiform attacks, and psychical disturbances. 



