GENERA INCERTAE SEDIS 247 



heart-shaped chitinoid body. Male unknown. Vulva a 

 little behind the middle of the body. A caudal gland present. 



Hab. Fresh water. 



Genotype : 31. haemispTiaericus v. Linstow, 1877. 



V. Linstow, 1877, Arch. f. Naturg., xliii, i, 2. 



According to Micoletzky (1922, Arch. f. Naturg., Abt. A, 

 Ixxxvii, 620) this is probably the larva of a parasitic form. The 

 fact that, although he only saw " undeveloped " females, v. 

 Linstow mentions the presence of a vulva, is somewhat opposed 

 to this view. In any case, the description is such that it is 

 impossible to determine the systematic position of the worm. 



18. Nema Leidy, 1856. 



" Body ascaridiform. Head without appendages. Mouth 

 unarmed, large, infundibuliform, oesophagus tubular, 

 membranous, expanding into a simple straight intestine ; 

 anus ventral. Tail conical, acute, recurved. Generative 

 aperture near the middle of the body." 



Hab. About dead specimens of a Phryganea. 

 Genotype : N . vacilans Leidy, 1856. 



Leidy, 1856, Proc. Acad. Nat. Sci. Philadelphia, viii, 49. 



19. Phacelura Ehrenberg, in Hemprich & Ehrenberg, 1831. 



Head not distinct. Tail with rounded tip, bearing four to 

 eight styliform appendages. 



Hab. Parasitic in fresh-water Snails. 

 Genotype : P. paludinae Ehrenberg, 1831. 



Ehrenberg, in Hemprich & Ehrenberg, 1831, Symbolae 

 Physicae, Pars Zool., Decas I, Appendix, Phytozoa Entozoa, 

 sig. a; Diesing, 1851, Systema Helminthum, ii, 137. 



20. Phanoglene Nordmann, 1840, nee Eberth, 1863. 



Body filiform, smooth, pointed behind. Mouth truncate, 

 bilabiate, provided with cirri. Neck marked with very red 

 eyes. Penis of male single. 



Hab. Genotype in the larva of a Neuropterous insect. 

 Genotype : P. micans Nordmann, 1840. 



Nordmann, in Lamarck, 1840, Hist. nat. des Animaux sans 

 Vertebres, 2nd ed., Paris, iii, 664. 



21. Phlyctainophora Steiner, 1921. 



Body stout, in the shape of an irregular, curled cylinder. 

 Cuticle with about fifteen more or less spherical vesicles, 

 almost symmetrically placed on the two sides of the body, 



