240 



BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



spiralis, is as follows : The eggs of the worm pass out in the droppings 

 and are eaten by sowbugs. The embryos escape and develop to in- 

 fective larvae in the body cavity. When infested sowbugs are eaten 

 by suitable birds, the larvae develop in them to adults. This work 

 is based on comparative studies, not on experimental feedings. 



Distribution. — North America (United States and Porto Rico), 

 Europe (Italy, France, Spain), Asia (Russian Turkestan), Africa 

 (Tunis), and Australia. In addition to the above localities may be 

 given Austria, Belgian Congo, and Algeria, as Railliet considers that 

 the reports of D. nasuta from these places are probably records of 

 D. spiralis. 



Figs. 302-303. — Dispharynx spiralis. 302, Female. After Piana, 1897. 303, 

 a, Head end. After Seurat, 1916. b, Ovejector. After Set; rat, 1919 



DISPHARYNX CAPITATA (Molin, 1860) Cram, 1927 



Synonyms. — Dispharagus capitatus Molin, 1860 ; Spiroptera alata 4 

 in Molin, 1860; Acuaria capitata (Molin, 1860) Railliet, Henry, and 

 Sisoff, 1912. 



Hosts. — Primary : Falco minutus; secondary : Unknown. 



L ocation. — Pro vent riculus. 



Morphology. — Dispharynx (p. 237) : Head conical, continuous with 

 body. Cordons markedly flexed, short, strongly recurrent, not 

 anastomosing. Mouth with 2 very small papilliform lips. Body 

 filiform and dense, with delicate transverse striations. 



Male unknown. 



Female 11 mm. long by 300/* wide. Posterior extremity conical, 

 apex obtuse. Anus not far from caudal extremity. 



Life history. — Unknown ; probably involves intermediate stages in 

 other hosts. 



Distribution. — South America (Brazil). 



* Catalogue of the Vienna Museum. 



