248 PARASITES OF MAN 



What, therefore, it may be asked, can be the cause of immunity 

 enjoyed by Icelanders in this respect ? The answer is not 

 apparent ; nevertheless Krabbe and Finsen have testified to the 

 fact that Iceland is the only country that is entirely free from 

 Ascaris lumbricoides. 



As remarked in my previous work the number of worms 

 present in any human bearer is usually small, varying commonly 

 from one to six or eight. Cases in which scores or hundreds 

 have existed are comparatively rare. Kiichenmeister mentions 

 the case of one child who passed 103 examples, and of another 

 child that harbored from 300 to 400 worms. Dr Gilli, of 

 Turin, gives a case where 510 were passed by a child, and 

 Cruveilhier estimated that over 1000 existed in an idiot girl, 

 whose intestines he found crammed with them. A remarkable 

 case has also been communicated to me by Dr Mackeith, of Sand- 

 hurst, Kent, who, by means of santonine, expelled from a little 

 girl, five and a half years of age, 300 lumbrici ; and I am like- 

 wise indebted to Dr Cooper Rose for notes of a case in which 

 about thirty lumbrici were expelled, chiefly in consequence of 

 the employment of this drug. The most interesting fact, how- 

 ever, in this case was that the child was only fifteen months old. 

 In this case the symptoms were severe. 



The proper habitat of the lumbricus is the upper and middle 

 part of the small intestine. From this situation it often wanders 

 into the stomach, and frequently gains access to the outer world, 

 not only by the natural passages of the mouth, nostrils, and 

 anus, but also, occasionally, in a more direct way, by perforating 

 the intestinal and abdominal walls. Many cases are on record 

 where lumbrici have passed into the abdominal cavity. In other 

 instances they have lodged themselves within the abdominal 

 viscera and pulmonary organs. When they find their way into 

 the parietes of the abdomen and adjacent parts, they usually give 

 rise to the formation of abscesses requiring surgical interference. 



As regards the symptoms produced by lumbrici, these vary 

 according to the situation they happen to occupy. The sym- 

 ptoms are also modified by age and temperament. In the 

 stomach and intestines they give rise to colic and shooting pains 

 about the abdomen, followed generally by dyspepsia, nasal itch- 

 ing, nausea, vomiting, and even diarrhoea. Occasionally death 

 supervenes suddenly. A singular case of this kind (the particu- 

 lars of which I only gathered from a local newspaper) occurred 

 in a boy, thirteen years of age, at the County Gaol at Hertford, 



