332 



THE ROUND WORMS 



wander 



eggs to be widely spread about the region of the anus. The worms may also wandc 

 into the vagina, urethra, or under prepuce. It will be seen that as a result of the 

 scratching, the fingers become contaminated with ova which may be carried to the 

 mouth and so cause a fresh infection, no intermediate host being required. The 

 examination of the material under the finger nails of children harboring this parasite 

 may show eggs under the microscope. A knowledge of the life history the early 

 location in the small intestine, and later on in the large shows that treatment should 

 be dual in its direction enemata for the gravid female in the rectum and santonin 

 and calomel for the young adults in the small intestine. 



The diagnosis is preferably made by examining the stools for the 

 white, thread-like females which are expelled after a diagnostic dose of 

 calomel and salts, rather than by searching for the eggs. 



These females, which are packed with embryo containing eggs, may be seen 

 wriggling on the surface of the freshly passed faeces. In handling these worms 

 one should be careful as they are apt to cause infection should the eggs get on the 

 fingers. 



ACANTHOCEPHALI 



These are called thorn-headed worms on account of a proboscis which projects 

 anteriorly like a little peg. 



There are several rows of hooks surrounding this projection which are directed 

 backward to enable the parasite to attach itself to the intestinal wall. The worm 

 absorbs nourishment through the general body wall, there being no alimentary 

 canal or mouth. These worms are common in hogs. The three-shelled eggs are very 

 striking and the intermediate stage is in June bugs. 



The Echinorhynchus or Gigantorhynchus gigas. This parasite is about 6 inches 

 (15 cm.) long for the male and 10 to 12 inches (25 cm.) for the female. It has 

 transverse rings and resembles Ascaris but is more white in color. It is said to be not 

 uncommon in southern Russia. 



The Echinorhynchus or Gigantorhynchus moniliformis might be contracted 

 by persons eating death-watch beetles as is sometimes done for the improvement of 

 the complexion. 



HIRUDINEI (LEECHES) 



Hirudo medicinalis. This is the leech used medicinally for the abstraction of 

 blood. They have a secretion which prevents coagulation of the blood so that when 

 they are removed the wound still continues to bleed. 



Limnatis nilotica. This species has been found in many parts of northern Africa 

 and, gaining access to the stomach through drinking water, it wanders to the phar- 

 ynx, nares, and even trachea. Manson refers to a case of obstinate epistaxis and 

 headache caused by a leech in the nostril. 



This leech is about 4 inches long (8 to 10 cm.) and about % inch (i.a cm.) broad. 

 The dorsal surface is greenish brown with narrow orange-brown borders. The young 

 leeches are only about ) inch (3 mm.) long and taken in with the drinking water 



