NEMATODA 217 



could be devised than Dracunculus, I thought it right to 

 combine Lister's and Gmelin's nomenclature as above, 1864. 

 Leuckart pursued a similar course, crediting Linneus with the 

 titles. 



The guinea- worm having been known from the earliest times, 

 it is not surprising that its true nature long remained a 

 mystery. Any one who has read Kiichenmei sterns elaborate 

 narrative of the historical significance of the Dracunculus will 

 hardly have failed to arrive at the conclusion that Moses was 

 probably the earliest writer on the endemic disorder which is 

 occasioned by this parasite. There can be no doubt that the 

 " fiery serpents" which afflicted the children of Israel during 

 their stay in the neighbourhood of the Red Sea were neither 

 more nor less than examples of our Dracunculus. It is further 

 evident that Plutarch spoke of Dracunculi, when in the eighth 

 book of his ' Symposiacon/ he quotes Agatharchidas as stating 

 that the people taken ill on the Bed Sea suffered from many 

 strange and unheard-of attacks, amongst other worms, from 

 " little snakes, which came out upon them, gnawed away their 

 legs and arms, and when touched retracted, coiled themselves 

 up in the muscles, and there gave rise to the most insupportable 

 pains." In order to render the passage more readable, it will 

 be seen that I have slightly altered the original version (' Para- 

 siten/ s. 305). 



The guinea-worm may be described as a nematode mea- 

 suring from one to six feet in length, having a thickness 

 of T ' 5 th of an inch. The body is uniformly cylindrical, termi- 

 nating below in a more or less curved and mucronately pointed 

 tail. The head is flatly convex or truncate, having a central, 

 simple mouth, which is surrounded by four equi-distantly and 

 cruciately disposed papillae. The mode of reproduction is 

 viviparous, the body enclosing a prodigious number of hatched 

 embryos, which, by distension of the uterine ducts, almost 

 entirely obliterate the somatic cavity. Notwithstanding the 

 statements of Owen to the contrary, the male Dracunculus is at 

 present altogether unknown. 



The guinea-worm possesses a comparatively limited geogra- 

 phical range, for not only is it proper to the tropical regions, 

 but within intertropical limits it is almost exclusively confined 

 to certain districts in Asia and Africa. Thus, according to 

 Kiinsenmuller, as quoted by Busk, it occurs endemically in Arabia 

 Petrsea, on the borders of the Persian Gulf and Caspian Sea, on the 



