ii8 INFECTIOUS AND PARASITIC DISEASES. 



her larvae the worm leaves her host spontaneously. The 

 embryos find their way into water, often, probably, when 

 the host is bathing, and as has been said, develop in the 

 water-flea cy clops. The adult worm is of considerable 

 size, measuring from 50 to 80 cubic centimeters (20-32 

 inches) in length and a few millimeters in breadth. It 

 is of a white or yellowish-brown color. When the 

 worm begins to come out it should be left alone at first, 

 as it may leave spontaneously. However, it can be ex- 

 tracted by catching the protruding head between the 

 split end of a smooth stick and winding it up on the lat- 

 ter, a few turns a day. This is known as the Soudanese 

 method of extraction. Care should be taken not to 

 break the worm during removal, as disastrous conse- 

 quences may follow rupture. 



The guinea-worm is widely distributed in tropical 

 and sub-tropical countries, but occurs most frequently 

 in Africa, Southern Asia, India, and Brazil. In places 

 where this parasite is known all water used for drinking 

 purposes should be boiled, and no uncooked vegetables 

 should be eaten. Also, since the possibility of the 

 worm entering the skin has not been definitely excluded, 

 baths should be taken in clear water only. 



Known quite generally as the filaria 

 T, sanminis hominis lives, as its name 



implies, in the blood. Only the embryos, 

 however, are really present in the blood, the adult 

 worms having their habitat in one of the larger lymph 



