248 BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



has recently found specimens agreeing with the descriptions of this 

 species, in Nettion carolinense and Anas rubripes, and is able to add 

 the following particulars: Male 8 to 10 mm. long by 300/a to 500/*. 

 wide. In a male 8 mm. long, cordons 500/* long by 20/* wide; 

 pharynx 133/*, esophagus 830/*, long ; cloacal aperture 330/* from pos- 

 terior end ; spicules 706/* and 208/* long, respectively. 



Female 12 to 18.5 mm. long. In a female 12 mm. long by 515/* 

 wide, the pharynx is 150/* long ; cordons 748/* long by 25/* wide ; vulva 

 1.3 mm., anus 250/*, from posterior end; eggs 37/* by 20/*. Vulva 1 

 to 1.4 mm. from tip of tail. Ovejector of type of Dispharynx 

 ovejector, composed of short vagina perpendicular to wall of body 

 and joining the ovejector proper ; this is directed posteriorly and is 

 divided into a vestibule and sphincter, the limit of which is marked 

 by a thickening of the muscular tunic. The sphincter passes directly 

 to the 2 branches of the trompe ; these extend parallel to the ovejector 

 to join the uteri ; the latter extend forward at first, twist into a loose 

 spiral, then separate, one continuing anteriorly while the other turns 

 and extends posteriorly. Numerous thick-shelled eggs. 



Life history. — According to Hamann, the eggs pass out in the 

 feces of birds and on getting to water may be swallowed by water 

 fleas, Daphnia pulex. In the intestine the embryo escapes from the 

 egg and makes its way to the body cavity, where it develops to an 

 infective larva 1.7 to 2 mm. long. When such infected water fleas 

 are eaten by suitable bird hosts, the worms develop to maturity. 



Distribution. — Europe (Germany and France) and Africa (Al- 

 geria) and North Anierica (United States). 



See the discussion of this species in connection with E. jugadornata 

 (p. 246). 



ECHINURIA ARDEAE (Smith, Fox, and White, 1908) Cram, 1927 



Synonyms. — Dispharagus ardeae Smith, Fox, and White, 1908; 

 Acuaria ardeae (Smith, Fox, and White, 1908) Ward, 1918. 



Hosts. — Primary: Ardea herodias; secondary: Unknown. 



Location. — Alimentary tract. 



Morphology. — Echinuria (p. 244) : Body slightly attenuated an- 

 teriorly. Cuticula rather coarsely striated transversely. Mouth 

 (fig. 311 a and b) with 2 prominent lateral lips, each with a pair of 

 papillae. Cordons originating at the base of the lips on each side, 

 passing posteriorly along the submedian lines to nearly the middle 

 of body length, then passing dorsally and ventrally, respectively, to 

 anastomose with the corresponding cordons from the opposite side. 



Male unknown. 



Female 17 mm. long by 700/* wide. Head 150/* wide at base of 

 lips. Anterior esophagus 800/* long by 50 to 90/* wide; posterior 



