479 



E. GORDIIDAE. 



VERY long thin worms similar to Filariae, which, in their adult condition, live 

 free in brooks, pools and springs ; the mouth and the commencement of the 

 intestine are obliterated ; there are no lateral ridges, and the muscular system 

 presents a structure different to that of the Nematoda. The posterior end of the 

 male is split, and spicules are lacking ; there are two testicles. In both sexes the 

 genitalia discharge through the terminal gut. 



The larvae, which carry a rostrum beset with hooks, force themselves into the 

 larvae of water-insects : more rarely they invade molluscs, and they then become 

 encysted within the body of the host. According to Villot, at least a part of them 

 attain the intestine of fishes, where they again become encysted, and after a period 

 of rest they travel into the tissues of their hosts, and finally again reach the exterior 

 by way of the intestine, where they then become adult. In most cases, however, 

 the 'gordius larvae are taken up by predacious water insects ; they live for a while 

 in the body cavity of these insects, undergo a metamorphosis, and finally wander 

 into the water. 



A few species invade man accidentally with water, in which case they are 

 usually vomited up : 



Gordius aquaticus, Dujardin, 30 to 90 cm. in length (Aldrovandi, Degland, 

 Siebold, Patruban). 



Gorditis tolosanus, Duj., n to 13 cm. in length (Fiori). 



Gordius varius, Leidy, 10 to 16 cm., female, up to 30 cm. in length (Diesing). 



Gordius chilensis, Blanch. (Guy). Gordius villoH, Rosa (Bercutti, Camerano) ; 

 Gordius tricuspidatus, L. Def. (R. Blanchard), Gorditts violaceus, Baird (Topsent), 

 and Gordius pustulosus, Baird (Parona). 







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