356 



BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



Male 2.125 mm. long hy 90> wide (fig. 418 a to d). Buccal-capsule 

 19/* long. Pharynx 225/* long. Esophagus 395/* long. Cervical pa- 

 pillae slightly posterior to nerve ring, which surrounds the middle 

 of the pharynx. Cloacal aperture 128/* from posterior extremity, 

 bounded by a chitinous projecting ring. Caudal papillae distributed 

 as follows : 2 pair preanal ; one small median papilla situated at the 

 center of the space which they bound ; 2 pair postanal, slightly asym- 

 metrical. Spicules of unequal length, the left one 1.187 mm. long, 

 the right one 75/* long. Tail tapering, ends in small button. 



Female forming cysts 2 mm. large. Body coiled in complex man- 

 ner (fig. 419 a to c). No longitudinal furrows as are found in spe- 

 cies of Tetrameres. Cuticle of anterior extremity folded to give 



Q/f7)f7) 



Figs. 417-418. — 417, Microtetrameres helix, a, Male tail; b and c, females; 

 d, female tail. Original. 418, Microtetrameres inermis. a, Male ; b, ven- 

 tral view and c, lateral view of tail of same ; d, head end of same. (Scale 



APPLIES TO b, C, AND d. ) AFTER SEURAT, 1913 



appearance of spy-glass (fig. 419d). Buccal capsule 20/* long. 

 Pharynx 300//, long (Linstow) or 260/* long (Seurat) by 40 /* wide. 

 Esophagus 1.125 mm. long (Seurat) or 2 mm. long (Linstow) by 

 24/* wide. Cervical papillae slightly posterior to nerve ring which 

 surrounds the middle of the pharynx. Intestine dark-brown. 

 Seurat (1913c) says that in the adult female the intestine is com- 

 pressed between the uteri, its walls almost pressed together, whereas 

 in the } 7 oung female the intestine is voluminous and entirely filled 

 with a maroon-colored mass which is undoubtedly a reserve supply of 

 material to be used later during egg formation. Anus 135/* from 

 posterior extremity. Vulva (fig. 420 6?) 95/* anterior to anus. Ves- 

 tibule of ovejector (fig. 420 a and 5) 875/* long. Trompe in the form 

 of a large reservoir 375/* long by 110/* wide, bifurcated at its end 

 where it joins the uteri. Seminal receptacle (fig. 420 c) piriform, of 



