172 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



acetabulum by two or three lateral loops of uterus; posterior testis 

 entirely behind anterior one. Cirrus sac elongated-oval, 0.15 to 0.27 

 nun. long by 0.07 to 0.11 mm. wide, containing much convoluted semi- 

 nal vesicle, ejaculatory duct and eversible cirrus. Ovary oval, 0.13 

 to 0.24 mm. long by 0.12 to 0.23 mm. wide, slightly submedially in po- 

 sition. Seminal receptacle globular, dorsal to caudal margin of ovary. 

 Vitellaria consisting of 10 to 12 large irregular follicles on each side 

 of body, in anterior half of body, just caudal to seminal receptacle. 

 Uterus greatly convoluted in descending and ascending, filling most of 

 postovarial portion of body, then passing anteriorly to left of ovary 

 and posterior testis and between testes to genital pore. Mature ova 

 dark brown, 36jli to 42/* long by 22/i, to 23ju, wide. 



Host. — Gi'us canadensis tahida (Peters). 



Habitat. — ^Liver. 



Locality. — Texas : Clodine. 



Type material.— {]. S. N. M. Helm. Coll. No. 36757. 



Remarks. — Brachylecithum gruis is described from pieces of seven 

 worms from the livers of two sandhill cranes, Grus canadensis tabida. 

 These birds died of a limberneck disease occurring in wintering birds 

 in the vicinity of Clodine, Tex., during January 1940. Only frag- 

 ments of the worm were available for study, although one nearly com- 

 plete worm is included in the collection. 



Brachylecithum gruis has an elongated, serpentine body and suckers 

 of approximately equal size, which, together with the elongated, dis- 

 tinctly lobed testes situated one entirely behind the other and a rela- 

 tively large oval ovary, distinguish it from other species of the genus. 



BRACHYLECITHUM SEIURICUM, new species 



Figure 37, a-f 



Diagnosis. — ^Body flattened dorsoventrally, elongated, 1.79 to 2.37 

 mm. long by 0.18 to 0.29 mm. wide in region between anterior testis 

 and vitellaria, with almost parallel sides and rounded or slightly ta- 

 pering extremities. Musculature of body weakly developed. Cuticle 

 thin, aspinose, with fine transverse ridges. Small sensory papillae on 

 margins of body in some specimens. Oral sucker subterminal to in- 

 conspicuous liplike protuberance, weakly muscular, 0.11 to 0.14 mm. 

 in diameter. Acetabulum weakly muscular, protrusible, 0.14 to 0.19 

 mm. in diameter, with shallow saucerlike lumen or with center pro- 

 truded far enough to obliterate lumen (fig. 37, 6) in anterior fourth 

 of body. Ratio of diameter of oral sucker to acetabulum 1 : 1.2 to 1.5. 

 Prepharynx absent. Pharynx muscular, globular, relatively small, 

 approximately 0.03 mm. in diameter. Esophagus very thin-walled, 

 slender, approximately 0.19 to 0.20 mm. long, bifurcating just in front 

 of or dorsal to cephalic margin of acetabulum. Ceca thin- walled, dif- 



