NEMATODA 



Order I. ASCAROIDEA Railliet & Henry, 1915. 



Free-living or parasitic forms having normally three lips, of 

 which one is dorsal and two subventral. In certain cases the 

 lips may be much reduced or absent. 



■ Fam. 1. ASCARIDAE Cobbold, 1864. 



Parasitic forms. Polymyarian. Lips well developed, bear- 

 ing papillae and sometimes alternating with three interlabia. 

 Buccal cavity absent. Reproductive organs highly developed. 

 Male with two spicules. Aii accessory piece present or absent. 

 Uterine branches parallel. Oviparous. Eggs very numerous, 

 with unsegmented contents when laid. 



Subfam. 1. ASCARINAE Travassos, 1913. 



Oesophagus without well-marked ventriculus, sometimes 

 with a muscular bulb. Spicules equal or subequal. Accessory 

 piece absent. Vagina and uterus run posteriorly from the 

 vulva. 



1. Ascaris L., 1758. 



Syn. Stomachida Pereboom, 1780; Fusaria Zeder, 1800; 

 Lombricoides Merat, 1821. 



Cervical alae absent. Lips with dentigerous ridges. Inter- 

 labia, if present, extremely reduced. No interlabial grooves 

 at bases of lips. Male with five or six pairs of postanal 

 papillae, the anterior pair or anterior pairs havihg double 

 terminations. Numerous irregularly-arranged preanal papil- 

 lae. Spicules non-alate, tubular, relatively short and stout. 

 Vulva near middle of body or anterior to it. Uterine branches 

 two. 



Hab. Small intestine of Mammals. 

 Genotype : A. lumbricoides L., 1758. 



Linnaeus, 1758, Systema Naturae, i, 644, 648. 



2. Ophidascaris Baylis, 1921. 



Cervical alae absent. Lips almost square. Dorsal lip 

 slightly smaller than ventro- lateral lips. Dentigerous ridges 



SYN. NEM. B 



