146 BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



thought preferable to place it in Porrocaecum where attention will 

 be drawn to it than to leave it in the genus Ascaris, which position 

 is known to be incorrect. 



PORROCAECUM ANGUILLAE (Linstow, 1899) Cram, 1927 



/Synonym. — Ascaris anguillae. 



Linstow described this as a larva from the eel, Anguilla vulgaris. 

 The larvae were rolled up and often encapsuled in the abdominal 

 organs. The adult may possibly be found in water birds; therefore 

 a brief description follows: Length of larva 38 mm., width 970/x. 

 Esophagus 1/9, tail 1/198 of total length, the tail rounded with a 

 small digitiform prolongation. The posterior 5/13 of the esophagus 

 (fig. 215a) is a ventriculus from which there is a cecum, anteriorly 

 directed, equal in length to the ventriculus, joining it to the intestine. 



Genus CONTRACAECUM Railliet and Henry, 1912 



Synonym. — Kathleena Leiper and Atkinson, 1914. 



Generic diagnosis. — Anasakinae (p. 135) : Esophagus with reduced 

 posterior ventriculus, giving off laterally a posteriorly directed 

 appendix. An intestinal cecum present. Interlabia present, usually 

 very well-developed. Dentigerous ridges usually absent. 



Parasitic in the proventriculus and intestine of fish-eating birds, 

 in intestine of mammals and of fishes. 



Type-species. — Contracaecum spiculigcrum (Rudolphi, 1809) 

 Railliet and Henry, 1912. 



Xi:V TU SI-KCIES OK CONTRACAECUM 



1. Male alone described 2. 



Both male and female, or female alone, described 3. 



2. Male 13 mm. long; esophageal appendix 700/* long; spicules 1.8 mm. long. 



Contracaecum engonium, p. 150. 



Male 1G.5 to 32.5 mm. long; esophageal appendix 960/t to 1.2 mm. long; 



spicules 4 mm. long Contracaecum punctatum, p. 157. 



3. Vulva posterior to middle of body dividing body length in ratio of 2 : 1. 



Contracaecum multipapillatum, p. 154. 

 Vulva anterior to middle of body 4. 



4. Female alone known; eggs 80 to 90/* long by 60/* wide; from Haliaetus 



species Contracaecum haliaeti, p. 150- 



Both male and female known ; eggs different from above ; from other hosts 

 than above 5 



5. Pulp of lips with 2 anteriorly directed bipartite processes; interlabia 



strongly curved, the anterior ends split into 2 rounded processes; male 

 witb 3 pairs of double postanal papillae. 



Contracaecum micropapillatum, p. 153. 

 Lips and interlabia different from above; male with more than 3 pairs 



of caudal papillae, and not all pairs double 6. 



G. Esophageal appendix not more than 1 mm. long 7. 



Esophageal appendix more than 1 mm. long 11. 



