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TREMATODE GEXUS BRACHYCOELIUM BYRD 193 



of the vitellaria, the larger suckers, the larger ovary and testes, and 

 the transverse looping of the uterus. From all other members of 

 the genus thus far mentioned it is separated by the transverse bridge 

 of vitellaria. The position and distribution of the vitellaria, the 

 size and ratio of the suckers, and the uterine pattern serve to sepa- 

 rate it from the remaining members of the genus. 



BRACHYCOELIUM LOUISIANAE. new species 



Plate 9, Figuee .3 



This species of fluke is represented by five specimens taken from 

 the small intestine of the salamander Amhystoma opacum^ collected 

 from the vicinity of Pearl River, La. 



Description.— Body decidedly elongated, spatulated, being broadly 

 rounded anteriorly and somewhat more pointed posteriorly, 2.04 imii 

 to 3.1 mm long by 0.72 mm wide. Cuticle relatively thin, armed 

 with fine spines anteriorly as far as middle of posttesticular portion 

 of body. Oral sucker subterminal, circular, 0.20 mm in diameter. 

 Acetabulum circular, 0.134 mm in diameter, well forward in anterior 

 third of body, 0.496 mm behind anterior body margin. Ratio of 

 sizes of oral sucker and acetabulum, approximately 3 : 2. Pre- 

 pharvTix present, short. Pharynx muscular, almost globular, 0.052 

 mm long by 0.069 mm wide. Esophagus nonmuscular, 0.17 mm long. 

 Caeca flask-shaped, 0.29 mm long by 0.125 mm wide, diverging 

 posterolaterad to end well in front of acetabulum, lined internally 

 by a rather heavy epithelium. Ovary transversely oval, 0.128 mm 

 long by 0.149 mm wide, usually left in position (right in one speci- 

 men observed), close behind end of caecum and slightly anterior to 

 level of acetabulum. Oviduct long. Ootype at about level of 

 equator of acetabulum. Laurer's canal, a spherical receptaculum 

 seminis. and shell gland present. Uterus a simple tube, greatly con- 

 voluted, descending limb forming transverse and oblique loops to 

 near posterior margin of body, ascending limb forming two or three 

 transverse loops in posterior body, then passing forward by short 

 loops on ovarian side to about middle of posttesticular region, here 

 again forming a series of complete transverse loops before passing 

 to genital pore. Metraterm weakly developed. Ova numerous, thick 

 shelled, operculated, fully embryonated Avhen oviposited, 30/x by 45/x. 

 Vitellaria follicular, dispersed superficially just under dorsal surface, 

 continuous from side to side, extending from level of anterior margin 

 of ovary to posterior boundary of oral sucker, overlapping entire 

 digestive tract. Yolk ducts converging just posterior to ootype, 

 forming a small crescent-shaped yolk reservoir. Genital pore ven- 

 tral, in midline just in front of acetabulum. Testes rather large, 

 lateral, opposite acetabulum, testis on side of body opposite ovary 



