242 S. J. JOHN&TON. 



the Government Bureau of Microbiology, Sydney. They 

 are moderate sized worms, elongated and flattened, varying 

 in length from 8*1 to 14*82 mm. and in breadth from 2*4 to 

 3*7 mm. They reach the maximum breadth some distance 

 behind the middle of the body and become gradually nar- 

 rower towards the anterior end which is pointed; and bluntly 

 rounded off at the posterior end, which is almost semi- 

 circular. Figure 24 is drawn from a specimen which does 

 not show the characteristic shape very well, as it had 

 undergone a good deal of contraction along the long axis 

 and bulging in the transverse in its preservation. But at 

 the time the drawing was made I had only two specimens 

 available for study, and this one exhibited the various 

 structures in the body more clearly than the other. 



The mouth opening is terminal; the mouth cavity or 

 rudimentary oral sucker is funnel-shaped and there is 

 practically no prepharynx. The mouth cavity has the 

 characteristic crescentic form in transverse sections owing 

 to the prominence that occurs on its dorsal wall. But the 

 pharynx is strongly muscular and measures 0*35 x 0*31 mm. 

 An oesophagus is practically absent, the forking of the 

 intestine proceeding directly from the posterior end of the 

 pharynx. The intestinal limbs, which are without cseca of 

 any kind, lie some distance from the lateral edges of the 

 body and practically parallel to them. 



The genital pore is in the middle line, immediately at 

 the posterior end of the pharynx. The cirrus sac is small 

 and club-shaped and projects a little way behind the intes- 

 tinal fork. 



The testes are very large, irregularly oval in shape and 

 lie obliquely, one in front of the other, in the bay of the 

 posterior commissural circuit of the intestine. The posterior 

 is larger, measuring 1*07 x 0*58 mm., while the anterior 

 measures 0*93 x 0*427 mm. 



