340 THE ANIMAL PARASITES OF MAN 



play a part in the distribution of the parasite similar to that demonstrated 

 by Grassi as taking place in the spread of the ova of Trichocephalus and 

 Tamia. 



The assumption of a direct development without an intermediary 

 host was first substantiated by Leuckart by experiments on 

 himself and three of his students ; about fourteen days after 

 swallowing the eggs the oxyuris has attained 6 7 mm. in length ; 

 Grassi, and later on Calandruccio, infected themselves by swallowing 

 adult female oxyuris, with the same results. 



LITERATURE. 



Vix, E. Ueber Entozoen bei Geisteskranken, insbes. iiber . . . Oxyuris ver- 



micularis. (Allg. Zeitschr. f. Psych., 1860, xvii., p. 149.) 

 STRICKER, W. Physpath. Bemerk. iib. Ox. verm. (Virchow's Arch., 1861, xxi., 



p. 360.) 

 FLOGEL, J. H. L. Ueb. d. Lippen einiger Oxyuris- Arten. (Z. f. w. Z., 1869, xix., 



p. 234.) 

 MICHELSON. Die Oberhaut der Genitocruralfalte u. ihre Umgebung als Brutstatte 



von Ox. verm. (Berl. klin. Wchnschrft., 1877, xiv., No. 33.) 

 GRASSI, B. I malefizi delle mosche. (Gaz. degli ospitali, 1883, No. 59.) 

 WINDELSCHMIDT, Ein Fall von langjahr. Reflex-Epilepsie in Folge von Ox. verm. 



(Allg. med. Centralztg., 1883, p. 606.) 

 PROSKAUER, TH. Embryonen von Oxyuris in der Nase. (Zeitsch. f. Ohrenhlkde, 



1891, xxi., p. 310.) 



GORDIACEA. 



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 90 cm. in length (Aldrovandi, Degland, 

 Siebold, Patruban). 



Gordius tolosanus, Duj., u 13 cm. in length (Fiori). 



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



Gordius chilensis, Blanch. (Guy). Gordius villoti, Rosa (Bercutti, Came- 

 rano) ; Gordius tricuspidatus , L. Def. (R. Blanchard), Gordius violaceus, 

 Baird (Topsent) and G. pustulosus, Baird (Parona). 



