BY s. .). .tOH?^sroN. 279 



At first sight, the worms looked like the free posterior seg- 

 ments of a tape-worm of the Phyllobothrium-type, and of that 

 nature I supposed them to be until I had made a microscopic 

 examination. 



This new find differs so much from known Trematodes, that I 

 must propose for it a new genus and subfamily. 



M o R E A u 1 1 N iE, new subfamily. 

 MoREAUiA MiRABiLis, gen. et sp.n. 



Diagnosis. — Middle-sized worms, with weak musculature, and 

 small suckers near one another. Body flattened, rectangular in 

 shape^ with the long axis of the rectangle representiiig the breadth 

 of the worm. Integument thin, devoid of spines. Pharynx and 

 CESophagus well marked; intestinal limbs reaching to the posterior 

 end. Excretory vesicle Y-shaped. Genital opening on the left 

 border near its middle, copulatory organs present ; muscular 

 cirrus-sac surrounding the large vesicula semirialis, well-marked 

 pars prostatica, and cirrus. Cirrus spiny. Testes large and 

 deeply lobed, with their long axes in a straight line, and the 

 lobed ovary between. Laurer's canal elongated, receptaculum 

 seminis wanting. Uterus fairly long, running from right to 

 left, with a capacious receptaculum-seminis-uterinum. Yolk- 

 glands intensively developed, filling up the region of the body 

 outside the intestinal limbs. Eggs few in number, large, oval, 

 thin-shelled, with operculum. 



Parasitic in Ornithorhynchus anatinns, in the small intestine. 



T3^pe-specimen in the Australian Museum, Sydney, No. W. 407. 



External Characters. — These worms are mainly rectangular in 

 shape, flat and thin dorsoventrally, with the long axis of the 

 rectangle representing the breadth of the worm, while the short 

 axis represents the length. While in some of the specimens the 

 anterior and posterior edges are comparatively straight, in others 

 the lateral wings are drawn forwards a little so as to form a 

 shallow double concavity in front, with a slight projection in 

 the middle, between the two, and a corresponding double con- 

 vexity behind(Fig.l). The oral sucker is situated on the ventral 

 aspect, near the middle of the anterior border. 



