FILARIOIDEA 193 



lateral ray short, not reaching the margin of the bursa. 

 Medio-lateral and postero -lateral rays parallel and fused 

 proximally. Externo-dorsal rays short and thick. Termina- 

 tions of dorsal ray bidigitate. Two large, sessile papillae are 

 situated almost on the lip of the cloaca. Prebursal papillae 

 also present. Spicules short, equal, bifurcate distally. 

 Accessory piece absent. Tail of female long and finger-shaped. 

 Uterine branches opposed. 



Hab. Wall of gizzard of Ducks and Geese. 



Genotype : E. [Strorigyhis] U7icinatum (Lundahl, 1848). 



Lundahl, 1848, Notis. Sdllsk. Fauna et Flora Fenn. Fork., 

 Helsingfors, (1) 283; Skrjabin, 1916, Ann. Mus. Zool. Petro- 

 gracl, xx, 461 ; Seurat, 1918, Bull. Mus. Hist, nat., Paris, (5) 

 345. 



3. Amphibiophilus Skrjabin, 1916. 



Buccal capsule resembles that of Amidostomum and is 

 furnished with a large, triangular, pointed denticle at its base. 

 Lateral rays of bursa originate from a common trunk, from 

 which the antero-lateral separates while the remaining rays 

 are still fused for some distance. Externo-dorsal rays arise 

 from the main stem of the dorsal ray. Dorsal ray cleft for 

 about a quarter of its length. Its terminations are tridigi- 

 tate. Spicules composed of a broad and flat anterior portion 

 and a narrow, cylindi'ical posterior portion, provided distally 

 with a small hook composed of two branches. Tail of female 

 slender and pointed. 



Hab. Alimentary tract of Amphibia. 

 Genotype : A. acanthocirratus Skrjabin, 1916. 



Skrjabin, 1916, Sci. Res. Zool. Exp. Brit. E. Africa (Dogiel 

 & Sokolow), 1914, Petrograd, i, (4) 38, 117. 



Order III. FILARIOIDEA Weinland, 1858. 



Parasitic forms with paired lateral lips, or with or without 

 prominent lip-like structures. Oesophagus without bulb, 

 but divided into a muscular anterior portion and a more 

 glandular posterior portion. Eggs contain embryos when laid 

 or hatch in utero. An intermediate host probably always 

 necessary for development. 



In endeavouring to simplify the classification of the two- 

 lipped forms, we have found it impossible to maintain many 

 of the groups that have been proposed. The prevailing 

 tendency to raise repeatedly the rank of comparatively small 

 groups, without taking a sufficiently broad view of the classi- 

 fication of the Nematodes as a whole, seems to have brought 



SYN. NEM. O 



