32 ASCAROIDEA 



of bod}^ between twenty-fifth and twenty-ninth rings. Com- 

 mon trunk of uterus rather short, running posteriorly. Uterine 

 branches parallel, running anteriorly. Oviparous. Eggs 

 oval, with rather thin shell. 



Hab. Intestine of a Myriopod (one species known). 

 Genotj^e : C. villensis Gilson, 1898. 



Gilson, 1898, La Cellule, xiv, 360. 



6. Isakis Lespes, 1856. 



Syn. Rhigonema Cobb, 1898. 



Mouth with three low lips, having denticulate inner edges. 

 Oesophagus short, with a prebulbar swelling and a spherical 

 posterior bulb. Tail conically pointed. Male without caudal 

 alae. Several pairs of preanal and postanal papillae present. 

 Spicules equal. No accessory piece. Vulva near middle of 

 body. Female genital tube apparently single. Ovary re- 

 flexed. Oviparous. 



Hab. Intestine of Insects, Myriopods and ( 1) Molluscs. 

 In the genot3rpe the young are parasitic in Termites, the 

 adults free-living. 



Genotype : /. migrans Lespes, 1856. 



Lespes, Ann. Sci. nat., Paris, Zool., v, 335; Cobb, 1898, 

 Agric. Gaz. N.8.W., Sydney, ix, 311 ; Railliet & Henry, 1916, 

 Compl. rend. Soc. Biol., Paris, Ixxix, 114. 



7, Odontogeton Allgen, 1921. 



Mouth opening in a slight depression. Head with a cuti- 

 cular cap ^\hich " partly forms the teeth of the mouth and 

 partly an outer ring of strongly-developed and backwardly- 

 directed hooks." Oesophagus with a posterior muscular 

 bulb. Tail of male with three pairs of postanal and one pair 

 of preanal papillae. Spicules equal. Vulva a little behind 

 the middle of the body. Uterine branches opposed. Ovaries 

 reflexed. 



Hab. Mouth of Wart-hog (one species known). 

 GenotyjDc : O. 'phacochoeri Allgen, 1921. 



Allgen, 1921, Zool. Anz., liii, 84. 



Fam. 6. ATRACTIDAE Travassos, 1920 (?). 



Parasitic forms. Lips three or six, sometimes not apparent. 

 Pharynx usually absent. The three-lipped forms may possess 

 eversible jaws or fringes of bristles. Oesophagus club-shaped, 

 muscular, relatively short, followed by a pyi-iform glandular 

 bulb, with a long anterior portion or neck, which is sometimes 

 narrower than the oesophagus proper. No cervical alae. 



