Parasites. 289 



in those regions. It has been shown that disorders of 

 the lymphatic system, especially in the tropics, are found 

 frequently associated with, if not caused by, Filaria. 

 Naevoid and ordinary elephantiasis arabum, chyluria, 

 haematuria, lymph varixand abscess, hydrocele, affeftions 

 of the cord and testis, diarrhoea, fever, cachexia, deterio- 

 ration of general health, certain skin diseases, deafness, 

 eye disease, have been ascribed to the existence of such 

 filaria, although it is not contended that they are always 

 so caused." Every case of chyluria which I have 

 come across in this colony, I have ascertained to be 

 associated with filaria in the blood ; but with regard to 

 elephantiasis, I have not been so successful. I have taken 

 several cases at random and failed to find filaria in the 

 blood. 



The Filaria sanguinis hominis is an extremely minute 

 parasite occurring in large numbers in the blood of 

 human beings usually affefted with certain peculiar 

 diseases, and almost always in those resident in tropical 

 climates; although a few cases have been recorded in 

 persons who have never lived in the tropics, and in certain 

 people who have been apparently otherwise quite 

 healthy. 



" Its average length is rs" (=0*34 mm.) ; its breadth 

 ■aeVo" (=0"007 mm.) or about equal to the diameter of a 

 red blood corpuscle. It is enclosed in a transparent 

 tubular sac, within which it can be seen to alternately 

 contra6t and elongate itself. This sac is extremely 

 delicate and translucent, and may sometimes, when the 

 worm has shortened itself more than usual, be seen 

 collapsed and folded like a ribbon, and the next moment 

 be instantaneously straightened again, by the extension 



