164 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



between suckers. Testes rounded to transversely oval, 0.11 to 0.26 

 mm. long by 0.12 to 0.31 mm. wide, situated slightly obliquely in 

 anterior third of body with zone of posterior testes entirely behind 

 that of anterior, a relative position retained even in greatly con- 

 tracted specimens. Vasa efferentia arising from dorsomedial surfaces 

 of testes, uniting just in front of anterior testis to form a long vas 

 deferens. Cirrus sac elongated-pyriform, 0.12 to 0.16 mm. long by 

 0.06 to 0.07 mm. wide, containing a coiled seminal vesicle, ejaculatory 

 duct surrounded by prostatic gland cells and a cirrus, which is usually 

 observed to be partly everted in preserved specimens. Cirrus sac 

 usually contiguous with anterior margin of acetabulum. Ovary trans- 

 versely oval, 0.08 to 0.15 mm. long by 0.08 to 0.18 mm. wide, submedial 

 in position close behind posterior testis. Seminal receptacle large, 

 globular, posterior to caudal margin of ovary. Mehlis' gland located 

 immediately posterior to seminal receptacle. Laurer's canal opening 

 to outside dorsally to posterior third of ovary. Vitellaria composed 

 of 8 to 15 large, oval follicles on each side of body, tending to fuse 

 in median line anteriorly, located just posterior to seminal receptacle. 

 Vitelline ducts arising from anterior vitelline follicles and uniting 

 medianly to form common yolk reservoir. Uterus much convoluted, 

 filling most of body posterior to ovary, usually following course of 

 cecum in ascending, sometimes leaving cecum to ascend on same side of 

 ovary and posterior testis. Uterus describing several, usually 3 to G, 

 lateral loops between anterior testis and acetabulum before ascending 

 to genital pore. Metraterm weakly muscular, equal in length to cirrus 

 sac. Mature ova dark brown, 29fi to 35/* long by 19/t to 24/* wide, 

 fully embryonated when oviposited. 



Host. — Cyanocitta cristata (Linnaeus). 



Habitat. — Liver and gall bladder. 



Localities.— Texas : Houston (type) ; Georgia : Augusta ; and North 

 Carolina : Highlands. 



Molhiscan hosts. — BulimvZus alternatus mariae ( Albers) , Deroceras 

 reticulatum (Miiller), and Z>ew(?er«s Zaeve (Miiller). 



Type specimen.— U. S. N. M. Helm. Coll. No. 36761. Additional 

 specimen. No. 36769. 



Remarks. — Lutstrema microstomum is recorded only from the blue 

 jay Cyanocitta cristata. Seven (27 percent) of the 26 specimens of 

 this host examined harbored from 1 to over 200 worms (average 42 

 per bird) . Lutztrema microstomum can be separated from L. monen- 

 teron,t\\Q only other member of the genus thus far encountered from 

 birds in the United States, by its smaller and much narrower body, 

 its relatively larger and more anteriorly situated acetabulum, its rela- 

 tively shorter cecum, its more tandem testes, the greater distance 

 between the acetabulum and testes, and the pattern of the uterus in 

 front of the anterior testis. 



