238 TRICHINELLOIDEA 



delicate membrane. Adults in the intestine give rise to 

 larvae which become encapsuled in the musculature of the 

 same host. 



1. Trichinella Railliet, 1895. 



Syn. Trichina Owen, 1835, nee Meigen, 1830. 



With the characters of the Subfamily. 



Hab. Adult in intestine of Mammals. Larvae encapsuled 

 in muscles of same host. 



Genoty|)e : T. [Trichina] sjriralis (Owen, 1835). 



Owen, 1835, Trans. Zool. Soc, London, i, 315 ; Railliet, 1895, 

 Traite de Zoologie me'dicale et agricole, Paris, 1303 ; Hall, 1916, 

 Proc. U.S. Nat. Mus., 1, 10. 



Subfam. 2. TRICHURINAE Ransom, 1911. 



Male with one spicule or, exceptionally, with only a spicule- 

 sheath. Eggs lemon-shaped, with thick shell and polar 

 opercula; their contents unsegmented when laid. Develop- 

 ment, so far as known, direct. 



1. Trichuris Roederer, 1761. 



Syn. Trichocephalos Goeze, 1782 ; Trichocephalns Schrank, 

 1788 ; Mastigodes Zeder, 1800, nee de Blainville, 1828. 



Oesophageal portion of body very slender, and longer than 

 the thicker posterior portion. Posterior extremity blunt 

 and rounded in both sexes. On the ventral surface of the 

 oesophageal portion there is a longitudinal " bacillary band." 

 Posterior portion of body of male curled dorsally. Spicule 

 in a protrusible prepuce-like sheath, of which the external 

 surface, when protruded, may be smooth or spiny. Vulva 

 in posterior portion of body, near its junction with the oesoph- 

 ageal portion. Eggs lemon-shaped, with thick, usually brown, 

 shells and polar opercula. 



Hab. Caecum of Mammals, forming burrows in the epi- 

 thelium, in which the anterior end is inserted. 

 Genotype : T. [Ascaris'] trichiura (L., 1771). 



Roederer, 1761, Gotting. Anz. v. gelehrt. Sachen, i, 243 ; and 

 1762, ii, 41 ; Hall, 1916, Proc. U.S. Nat. Mus., 1, 20. 



2. Capillaria Zeder, 1800. 



Syii. Trichosoma Rudolphi, 1819 ; Trichosommn Crepliii, 

 1839; Calodium DujardLn, 1845; Thominx Dujardin, 1845; 

 Lmisc?ts Dujardin, 1845; JS'^^coZews Dujardin, 1845. 



Body very slender. Oesophageal portion shorter than, or 

 rarely equal in length to, the posterior portion. A longi- 



