TREMATODES OF AUSTRALIAN BIRDS. 229 



the pharynx. But instead of running backwards near the 

 edges of the body they course much nearer the middle line, 

 especially in the middle third of the body. They are not 

 straight but thrown into a number of waves. 



The genital pore is in the middle line, just in front of the 

 anterior testis, at the junction of the middle and posterior 

 thirds of the body. From the genital opening, the male 

 duct leads at first directly forwards, through the rudi- 

 mentary cirrus sac, and then bends sharply back and runs 

 towards the testes. This part of the duct is the vesicula 

 seminalis; and, just in the region where the bend occurs, a 

 number of prostate cells are attached to it, with their 

 bodies lying free in the parenchyma; only the anterior end 

 of the vesicula seminalis, where it joins the ejaculatory 

 duct lies within the cirrus sac. 



The testes are large and some distance apart, with a 

 distinct space between them and the ovary, which lies 

 between and somewhat to one side of the middle line. The 

 posterior testis is always more elongated than the anterior, 

 measuring, in a specimen 4*75 mm. long, 0*582 mm. x 0*291 

 mm., while the latter measures 0*427 x 0*33 mm. The long 

 axis of the posterior testis lies longitudinally, while that 

 of the anterior is rather oblique. The ovary is also oval in 

 shape, measuring in the same worm 0*291 x 0*232 mm. 



The ascending loop of the uterus is thrown into a number 

 of transverse coils which pass outwards beyond the intestinal 

 limbs into the field in which the yolk glands lie. The latter 

 consist of a large number of small follicles arranged in two 

 elongated fields, extending from the posterior edge of the 

 ventral sucker in front to the posterior edge of the ovary 

 behind. They do not cross over the intestinal limbs, but 

 are confined to the space between these limbs and the 

 lateral edges of the body. 



